[ { "id": "authors:xpcf5-99v38", "collection": "authors", "collection_id": "xpcf5-99v38", "cite_using_url": "https://authors.library.caltech.edu/records/xpcf5-99v38", "type": "article", "title": "Fading into Darkness: A Weak Mass Ejection and Low-efficiency Fallback Accompanying Black Hole Formation in M31-2014-DS1", "author": [ { "family_name": "De", "given_name": "Kishalay", "orcid": "0000-0002-8989-0542" }, { "family_name": "MacLeod", "given_name": "Morgan", "orcid": "0000-0002-1417-8024" }, { "family_name": "Jencson", "given_name": "Jacob E.", "orcid": "0000-0001-5754-4007", "clpid": "Jencson-Jacob-E" }, { "family_name": "Lau", "given_name": "Ryan M.", "clpid": "Lau-Ryan-M" }, { "family_name": "Antoni", "given_name": "Andrea", "orcid": "0000-0003-3062-4773" }, { "family_name": "Colmenares", "given_name": "Mar\u00eda Jos\u00e9", "orcid": "0000-0002-5296-6232" }, { "family_name": "Huang", "given_name": "Jane", "orcid": "0000-0001-6947-6072" }, { "family_name": "Masterson", "given_name": "Megan", "orcid": "0000-0003-4127-0739" }, { "family_name": "Karambelkar", "given_name": "Viraj R.", "orcid": "0000-0003-2758-159X" }, { "family_name": "Kasliwal", "given_name": "Mansi M.", "orcid": "0000-0002-5619-4938", "clpid": "Kasliwal-M-M" }, { "family_name": "Loeb", "given_name": "Abraham", "orcid": "0000-0003-4330-287X" }, { "family_name": "Panagiotou", "given_name": "Christos", "orcid": "0009-0001-9034-6261" }, { "family_name": "Quataert", "given_name": "Eliot", "orcid": "0000-0001-9185-5044" } ], "abstract": "

Stellar-mass black holes (BHs) can form from the near-complete collapse of massive stars, causing them to abruptly disappear. The star M31-2014-DS1 in the Andromeda galaxy was reported to exhibit such a disappearance between 2014 and 2022, with properties consistent with the failed explosion of an ≈12–13 M\u2299 yellow supergiant leading to the formation of an ≈5 M\u2299 BH. We present mid-infrared (MIR) observations of the remnant obtained with the James Webb Space Telescope (JWST) and X-ray observations from the Chandra X-ray Observatory in 2024. The JWST Mid-infrared Instrument/NIRSpec data reveal an extremely red source, showing strong blueshifted absorption from molecular gas (CO, CO2, H2O, SO2) and deep silicate dust features. Modeling the dust continuum confirms continued bolometric fading of the central source to log (L/L\u2299) ≈ 3.88 (≈7%–8% of the progenitor luminosity), surrounded by a dust shell spanning ≈40–200 au. Modeling of the molecular gas indicates ∼0.1 M\u2299 of gas expanding at ≈100 km s−1 near the inner edge of the dust shell. No X-ray source is detected down to a luminosity limit of LX \u2272 1.5 × 1035 erg s−1. We show that the panchromatic observations are explained by (i) a low-energy (≈1046 erg) ejection of the outer H-rich progenitor envelope and (ii) a fading central BH powered by inefficient (∼0.1% in mass) accretion of loosely bound fallback material. The analysis robustly establishes the bolometric fading of M31-2014-DS1 following its >30 yr archival record of constant optical/infrared brightness, and provides the first cohesive insights into BH formation via low-energy explosions and long-term fallback.

", "doi": "10.3847/2041-8213/ae468d", "issn": "2041-8205", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal Letters", "publication_date": "2026-03-10", "series_number": "2", "volume": "999", "issue": "2", "pages": "L25" }, { "id": "authors:rqf3c-c0g21", "collection": "authors", "collection_id": "rqf3c-c0g21", "cite_using_url": "https://authors.library.caltech.edu/records/rqf3c-c0g21", "type": "article", "title": "Hot Springs and Dust Reservoirs: JWST Reveals the Dusty, Molecular Aftermath of Extragalactic Stellar Mergers", "author": [ { "family_name": "Karambelkar", "given_name": "Viraj", "orcid": "0000-0003-2758-159X", "clpid": "Karambelkar-Viraj" }, { "family_name": "Kasliwal", "given_name": "Mansi M.", "orcid": "0000-0002-5619-4938", "clpid": "Kasliwal-M-M" }, { "family_name": "Lau", "given_name": "Ryan M.", "clpid": "Lau-Ryan-M" }, { "family_name": "Jencson", "given_name": "Jacob E.", "orcid": "0000-0001-5754-4007", "clpid": "Jencson-Jacob-E" }, { "family_name": "Blagorodnova", "given_name": "Nadejda", "orcid": "0000-0003-0901-1606" }, { "family_name": "G\u00f3mez-Mu\u00f1oz", "given_name": "Marco A.", "orcid": "0000-0002-3938-4211" }, { "family_name": "Tranin", "given_name": "Hugo", "orcid": "0000-0001-6314-8131" }, { "family_name": "Wavasseur", "given_name": "Maxime" }, { "family_name": "Shahbandeh", "given_name": "Melissa", "orcid": "0000-0002-9301-5302" }, { "family_name": "De", "given_name": "Kishalay", "orcid": "0000-0002-8989-0542" } ], "abstract": "
\n

We present James Webb Space Telescope (JWST) observations of four luminous red novae (LRNe): dusty, extragalactic transients from stellar mergers following common-envelope evolution (CEE) in massive binary stars. Our targets—AT 2021blu, AT 2021biy, AT 2018bwo, and M31-LRN-2015—span a broad range in progenitor primary masses (≈3–24 M\u2299) and post-merger ages (≈1100–3700 days). All four were observed with the Mid-Infrared Instrument from 5 to 25 μm; AT 2021blu and AT 2021biy additionally have 5–12 μm spectra from the Low-Resolution Spectrometer. These spectra show strong features of oxygen-rich molecules, including water vapor, supporting the recent association of water fountain sources with CEE. Radiative transfer modeling of the spectral energy distributions yields dust masses of ≈4.2 × 10−5, 3 × 10−4, 7.5 × 10−5, and 7.7 × 10−4 M\u2299, respectively—corresponding to ≈10%, 60%, 6%, and 12% of median dust masses in core-collapse supernovae (CCSNe) at similar phases. Accounting for their occurrence rates, we estimate that LRNe can contribute ∼25% as much dust as CCSNe to the cosmic dust budget. Furthermore, the lower expansion velocities of LRNe may reduce dust destruction by reverse shocks compared to CCSNe, potentially increasing this contribution. In addition to dust masses, we use our JWST observations to measure late-time properties such as the luminosities, temperatures, radii, and dust-to-gas ratios of the merger remnants. Our results highlight the need for broader infrared studies of LRNe to quantify their contribution to the cosmic dust budget, study the evolution of oxygen-rich molecules, and probe the final fates of CEE.

\n
", "doi": "10.3847/1538-4357/ae38bf", "issn": "0004-637X", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal", "publication_date": "2026-03-01", "series_number": "1", "volume": "999", "issue": "1", "pages": "16" }, { "id": "authors:b2g0v-aj215", "collection": "authors", "collection_id": "b2g0v-aj215", "cite_using_url": "https://authors.library.caltech.edu/records/b2g0v-aj215", "type": "article", "title": "Constraining Properties of Dust Formed in Wolf\u2013Rayet Binary WR 112 Using Mid-infrared and Millimeter Observations", "author": [ { "family_name": "Wu", "given_name": "Donglin", "orcid": "0009-0008-8224-3140" }, { "family_name": "Han", "given_name": "Yinuo", "orcid": "0000-0002-2106-0403", "clpid": "Han-Yinuo" }, { "family_name": "Williams", "given_name": "Peredur M.", "orcid": "0000-0002-8092-980X" }, { "family_name": "Onaka", "given_name": "Takashi", "orcid": "0000-0002-8234-6747" }, { "family_name": "Callingham", "given_name": "Joseph R.", "orcid": "0000-0002-7167-1819" }, { "family_name": "Hankins", "given_name": "Matthew J.", "orcid": "0000-0001-9315-8437" }, { "family_name": "Tuthill", "given_name": "Peter", "orcid": "0000-0001-7026-6291" }, { "family_name": "Lau", "given_name": "Ryan M.", "orcid": "0000-0003-0778-0321", "clpid": "Lau-Ryan-M" }, { "family_name": "Weigelt", "given_name": "Gerd", "orcid": "0000-0001-9754-2233" }, { "family_name": "Pope", "given_name": "Benjamin J. S.", "orcid": "0000-0003-2595-9114" }, { "family_name": "Richardson", "given_name": "Noel D.", "orcid": "0000-0002-2806-9339" }, { "family_name": "Moffat", "given_name": "Anthony", "orcid": "0000-0002-4333-9755" } ], "abstract": "

Binaries that host a carbon-rich Wolf–Rayet (WC) star and an OB-type companion can be copious dust producers. Yet the properties of dust, particularly the grain size distribution, in these systems remain uncertain. We present Band 6 observations of WR 112 by the Atacama Large Millimeter/submillimeter Array telescope (ALMA), which are the first millimeter observations of a WC binary system capable of resolving its dust emission. By combining ALMA observations with James Webb Space Telescope images, we were able to analyze the spatially resolved spectral energy distribution (SED) of WR 112. We found that the SEDs are consistent with emissions from hydrogen-poor amorphous carbon grains. Notably, our results also suggest that the majority of grains in the system have radii below one micrometer, and the extended dust structures are dominated by nanometer-sized grains. Among four parameterizations of the grain radius distribution that we tested, a bimodal distribution, with abundant nanometer-sized grains and a secondary population of 0.1 μ m grains, best reproduces the observed SED. This bimodal distribution helps to reconcile the previously conflicting grain size estimates reported for WR 112 and for other WC systems. We hypothesize that dust destruction mechanisms such as radiative torque disruption and radiative-driven sublimation are responsible for driving the system to the bimodal grain size distribution.

", "doi": "10.3847/1538-4357/ae31f1", "issn": "0004-637X", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal", "publication_date": "2026-03-01", "series_number": "1", "volume": "999", "issue": "1", "pages": "32" }, { "id": "authors:52nsj-em211", "collection": "authors", "collection_id": "52nsj-em211", "cite_using_url": "https://authors.library.caltech.edu/records/52nsj-em211", "type": "article", "title": "The Formation and Evolution of Dust in the Colliding-wind Binary Apep Revealed by JWST", "author": [ { "family_name": "Han", "given_name": "Yinuo", "orcid": "0000-0002-2106-0403", "clpid": "Han-Yinuo" }, { "family_name": "White", "given_name": "Ryan M. T.", "orcid": "0009-0006-7054-0880" }, { "family_name": "Callingham", "given_name": "Joseph R.", "orcid": "0000-0002-7167-1819" }, { "family_name": "Lau", "given_name": "Ryan M.", "orcid": "0000-0003-0778-0321", "clpid": "Lau-Ryan-M" }, { "family_name": "Pope", "given_name": "Benjamin J. S.", "orcid": "0000-0003-2595-9114" }, { "family_name": "Richardson", "given_name": "Noel D.", "orcid": "0000-0002-2806-9339" }, { "family_name": "Tuthill", "given_name": "Peter G.", "orcid": "0000-0001-7026-6291" } ], "abstract": "

Carbon-rich Wolf–Rayet (W-R) stars are significant contributors of carbonaceous dust to the galactic environment; however, the mechanisms and conditions for formation and subsequent evolution of dust around these stars remain open questions. Here we present JWST observations of the W-R+W-R colliding-wind binary Apep, which reveal an intricate series of nested concentric dust shells that are abundant in detailed substructure. The striking regularity in these substructures between successive shells suggests an exactly repeating formation mechanism combined with a highly stable outflow that maintains a consistent morphology even after reaching 0.6 pc (assuming a distance of 2.4 kpc) into the interstellar medium. The concentric dust shells show subtle deviations from spherical outflow, which could reflect orbital modulation along the eccentric binary orbit or nonsphericity in the stellar wind. Tracking the evolution of dust across the multitiered structure, we measure the dust temperature evolution that can broadly be described assuming an amorphous carbon composition in radiative thermal equilibrium with the central stars. The temperature profile and orbital period place new distance constraints that support Apep being at a greater distance than previously estimated, reducing the line-of-sight and sky-plane wind speed discrepancy previously thought to characterize the system.

", "doi": "10.3847/1538-4357/ae12e5", "issn": "0004-637X", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal", "publication_date": "2025-11-20", "series_number": "1", "volume": "994", "issue": "1", "pages": "122" }, { "id": "authors:ta0d7-8n387", "collection": "authors", "collection_id": "ta0d7-8n387", "cite_using_url": "https://authors.library.caltech.edu/records/ta0d7-8n387", "type": "article", "title": "A First Look with JWST Aperture Masking Interferometry: Resolving Circumstellar Dust around the Wolf\u2013Rayet Binary WR 137 beyond the Rayleigh Limit", "author": [ { "family_name": "Lau", "given_name": "Ryan M.", "orcid": "0000-0003-0778-0321", "clpid": "Lau-Ryan-M" }, { "family_name": "Hankins", "given_name": "Matthew J.", "orcid": "0000-0001-9315-8437" }, { "family_name": "Sanchez-Bermudez", "given_name": "Joel", "orcid": "0000-0002-9723-0421" }, { "family_name": "Thatte", "given_name": "Deepashri", "orcid": "0000-0002-1536-7193" }, { "family_name": "Soulain", "given_name": "Anthony", "orcid": "0000-0001-7661-5130" }, { "family_name": "Cooper", "given_name": "Rachel A.", "orcid": "0000-0001-7864-308X" }, { "family_name": "Sivaramakrishnan", "given_name": "Anand", "orcid": "0000-0003-1251-4124" }, { "family_name": "Corcoran", "given_name": "Michael F.", "orcid": "0000-0002-7762-3172" }, { "family_name": "Greenbaum", "given_name": "Alexandra Z.", "orcid": "0000-0002-7162-8036", "clpid": "Greenbaum-Alexandra-Z" }, { "family_name": "Gull", "given_name": "Theodore R." }, { "family_name": "Han", "given_name": "Yinuo" }, { "family_name": "Jones", "given_name": "Olivia C.", "orcid": "0000-0003-4870-5547" }, { "family_name": "Madura", "given_name": "Thomas", "orcid": "0000-0001-7697-2955" }, { "family_name": "Moffat", "given_name": "Anthony F. J.", "orcid": "0000-0002-4333-9755" }, { "family_name": "Morris", "given_name": "Mark R.", "orcid": "0000-0002-6753-2066" }, { "family_name": "Onaka", "given_name": "Takashi", "orcid": "0000-0002-8234-6747" }, { "family_name": "Russell", "given_name": "Christopher M. P." }, { "family_name": "Richardson", "given_name": "Noel D.", "orcid": "0000-0002-2806-9339" }, { "family_name": "Smith", "given_name": "Nathan", "orcid": "0000-0001-5510-2424" }, { "family_name": "Tuthill", "given_name": "Peter", "orcid": "0000-0001-7026-6291" }, { "family_name": "Volk", "given_name": "Kevin" }, { "family_name": "Weigelt", "given_name": "Gerd", "orcid": "0000-0001-9754-2233" }, { "family_name": "Williams", "given_name": "Peredur M.", "orcid": "0000-0002-8092-980X" } ], "abstract": "
\n

We present infrared aperture-masking interferometry (AMI) observations of newly formed dust from the colliding winds of the massive binary Wolf–Rayet system WR 137 with JWST using the Near Infrared Imager and Slitless Spectrograph (NIRISS). NIRISS AMI observations of WR 137 and a point-spread function calibrator star, HD 228337, were taken using the F380M and F480M filters in 2022 July and August as part of the Director's Discretionary Early Release Science program #1349. Interferometric observables (squared visibilities and closure phases) from the WR 137 \"interferogram\" were extracted and calibrated using three independent software tools: ImPlaneIA, AMICAL, and SAMpip. The analysis of the calibrated observables yielded consistent values except for slightly discrepant closure phases measured by ImPlaneIA. Based on all three sets of calibrated observables, images were reconstructed using three independent software tools: BSMEM, IRBis, and SQUEEZE. All reconstructed image combinations generated consistent images in both F380M and F480M filters. The reconstructed images of WR 137 reveal a bright central core with a ∼300 mas linear filament extending to the northwest. A geometric colliding-wind model with dust production constrained to the orbital plane of the binary system and enhanced as the system approaches periapsis provided a general agreement with the interferometric observables and reconstructed images. Based on a colliding-wind dust condensation analysis, we suggest that dust formation within the orbital plane of WR 137 is induced by enhanced equatorial mass loss from the rapidly rotating O9 companion star, whose axis of rotation is aligned with that of the orbit.

\n
", "doi": "10.3847/1538-4357/ad192c", "issn": "0004-637X", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal", "publication_date": "2024-03-10", "series_number": "2", "volume": "963", "issue": "2", "pages": "127" }, { "id": "authors:cdhpk-xte75", "collection": "authors", "collection_id": "cdhpk-xte75", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230602-251894000.48", "type": "article", "title": "An infrared transient from a star engulfing a planet", "author": [ { "family_name": "De", "given_name": "Kishalay", "orcid": "0000-0002-8989-0542", "clpid": "De-Kishalay" }, { "family_name": "Macleod", "given_name": "Morgan", "orcid": "0000-0002-1417-8024", "clpid": "Macleod-Morgan" }, { "family_name": "Karambelkar", "given_name": "Viraj", "orcid": "0000-0003-2758-159X", "clpid": "Karambelkar-Viraj-R" }, { "family_name": "Jencson", "given_name": "Jacob E.", "orcid": "0000-0001-5754-4007", "clpid": "Jencson-Jacob-E" }, { "family_name": "Chakrabarty", "given_name": "Deepto", "orcid": "0000-0001-8804-8946", "clpid": "Chakrabarty-Deepto" }, { "family_name": "Conroy", "given_name": "Charlie", "orcid": "0000-0002-1590-8551", "clpid": "Conroy-Charlie" }, { "family_name": "Dekany", "given_name": "Richard", "orcid": "0000-0002-5884-7867", "clpid": "Dekany-Richard-G" }, { "family_name": "Eilers", "given_name": "Anna-Christina", "orcid": "0000-0003-2895-6218", "clpid": "Eilers-Anna-Christina" }, { "family_name": "Graham", "given_name": "Matthew J.", "orcid": "0000-0002-3168-0139", "clpid": "Graham-M-J" }, { "family_name": "Hillenbrand", "given_name": "Lynne A.", "clpid": "Hillenbrand-L-A" }, { "family_name": "Kara", "given_name": "Erin", "orcid": "0000-0003-0172-0854", "clpid": "Kara-Erin" }, { "family_name": "Kasliwal", "given_name": "Mansi M.", "orcid": "0000-0002-5619-4938", "clpid": "Kasliwal-M-M" }, { "family_name": "Kulkarni", "given_name": "S. R.", "orcid": "0000-0001-5390-8563", "clpid": "Kulkarni-S-R" }, { "family_name": "Lau", "given_name": "Ryan M.", "orcid": "0000-0003-0778-0321", "clpid": "Lau-Ryan-M" }, { "family_name": "Loeb", "given_name": "Abraham", "orcid": "0000-0003-4330-287X", "clpid": "Loeb-Abraham" }, { "family_name": "Masci", "given_name": "Frank J.", "orcid": "0000-0002-8532-9395", "clpid": "Masci-Frank-J" }, { "family_name": "Medford", "given_name": "Michael S.", "orcid": "0000-0002-7226-0659", "clpid": "Medford-Michael-S" }, { "family_name": "Meisner", "given_name": "Aaron M.", "orcid": "0000-0002-1125-7384", "clpid": "Meisner-Aaron-M" }, { "family_name": "Patel", "given_name": "Nimesh", "orcid": "0000-0002-6021-9421", "clpid": "Patel-Nimesh" }, { "family_name": "Quiroga-Nu\u00f1ez", "given_name": "Luis Henry", "orcid": "0000-0002-9390-955X", "clpid": "Quiroga-Nu\u00f1ez-Luis-Henry" }, { "family_name": "Riddle", "given_name": "Reed L.", "orcid": "0000-0002-0387-370X", "clpid": "Riddle-Reed-L" }, { "family_name": "Rusholme", "given_name": "Ben", "orcid": "0000-0001-7648-4142", "clpid": "Rusholme-Benjamin" }, { "family_name": "Simcoe", "given_name": "Robert A.", "orcid": "0000-0003-3769-9559", "clpid": "Simcoe-Robert-A" }, { "family_name": "Sjouwerman", "given_name": "Lor\u00e1nt O.", "orcid": "0000-0003-3096-3062", "clpid": "Sjouwerman-Lor\u00e1nt-O" }, { "family_name": "Teague", "given_name": "Richard", "orcid": "0000-0003-1534-5186", "clpid": "Teague-Richard" }, { "family_name": "Vanderburg", "given_name": "Andrew", "orcid": "0000-0001-7246-5438", "clpid": "Vanderburg-Andrew" } ], "abstract": "Planets with short orbital periods (roughly under 10\u2009days) are common around stars like the Sun. Stars expand as they evolve and thus we expect their close planetary companions to be engulfed, possibly powering luminous mass ejections from the host star. However, this phase has never been directly observed. Here we report observations of ZTF SLRN-2020, a short-lived optical outburst in the Galactic disk accompanied by bright and long-lived infrared emission. The resulting light curve and spectra share striking similarities with those of red novae\u2014a class of eruptions now confirmed to arise from mergers of binary stars. Its exceptionally low optical luminosity (approximately 1035\u2009erg\u2009s\u207b\u00b9) and radiated energy (approximately 6.5\u2009\u00d7\u200910\u2074\u00b9\u2009erg) point to the engulfment of a planet of fewer than roughly ten Jupiter masses by its Sun-like host star. We estimate the Galactic rate of such subluminous red novae to be roughly between\u20090.1 and several per year. Future Galactic plane surveys should routinely identify these, showing the demographics of planetary engulfment and the ultimate fate of planets in the inner Solar System.", "doi": "10.1038/s41586-023-05842-x", "issn": "0028-0836", "publisher": "Nature Publishing Group", "publication": "Nature", "publication_date": "2023-05-04", "series_number": "7959", "volume": "617", "issue": "7959", "pages": "55-60" }, { "id": "authors:b4xqh-ycg18", "collection": "authors", "collection_id": "b4xqh-ycg18", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230227-902482000.2", "type": "article", "title": "Nested dust shells around the Wolf\u2013Rayet binary WR 140 observed with JWST", "author": [ { "family_name": "Lau", "given_name": "Ryan M.", "orcid": "0000-0003-0778-0321", "clpid": "Lau-Ryan-M" }, { "family_name": "Hankins", "given_name": "Matthew J." }, { "family_name": "Han", "given_name": "Yinuo" }, { "family_name": "Argyriou", "given_name": "Ioannis", "orcid": "0000-0003-2820-1077" }, { "family_name": "Corcoran", "given_name": "Michael F.", "orcid": "0000-0002-7762-3172" }, { "family_name": "Eldridge", "given_name": "Jan J.", "orcid": "0000-0002-1722-6343" }, { "family_name": "Endo", "given_name": "Izumi", "orcid": "0000-0002-9129-5988" }, { "family_name": "Fox", "given_name": "Ori D.", "orcid": "0000-0003-2238-1572" }, { "family_name": "Garcia Marin", "given_name": "Macarena" }, { "family_name": "Gull", "given_name": "Theodore R.", "orcid": "0000-0002-6851-5380" }, { "family_name": "Jones", "given_name": "Olivia C.", "orcid": "0000-0003-4870-5547" }, { "family_name": "Hamaguchi", "given_name": "Kenji", "orcid": "0000-0001-7515-2779" }, { "family_name": "Lamberts", "given_name": "Astrid", "orcid": "0000-0001-8740-0127" }, { "family_name": "Law", "given_name": "David R.", "orcid": "0000-0002-9402-186X" }, { "family_name": "Madura", "given_name": "Thomas", "orcid": "0000-0001-7697-2955" }, { "family_name": "Marchenko", "given_name": "Sergey V." }, { "family_name": "Matsuhara", "given_name": "Hideo" }, { "family_name": "Moffat", "given_name": "Anthony F. J.", "orcid": "0000-0002-4333-9755" }, { "family_name": "Morris", "given_name": "Mark R.", "orcid": "0000-0002-6753-2066" }, { "family_name": "Morris", "given_name": "Patrick W.", "orcid": "0000-0002-5186-4381", "clpid": "Morris-Patrick-W" }, { "family_name": "Onaka", "given_name": "Takashi", "orcid": "0000-0002-8234-6747" }, { "family_name": "Ressler", "given_name": "Michael E.", "orcid": "0000-0001-5644-8830", "clpid": "Ressler-Michael-E" }, { "family_name": "Richardson", "given_name": "Noel D.", "orcid": "0000-0002-2806-9339" }, { "family_name": "Russell", "given_name": "Christopher M. P.", "orcid": "0000-0002-9213-0763" }, { "family_name": "Sanchez-Bermudez", "given_name": "Joel", "orcid": "0000-0002-9723-0421" }, { "family_name": "Smith", "given_name": "Nathan", "orcid": "0000-0001-5510-2424" }, { "family_name": "Soulain", "given_name": "Anthony", "orcid": "0000-0001-7661-5130" }, { "family_name": "Stevens", "given_name": "Ian R.", "orcid": "0000-0001-7673-4340" }, { "family_name": "Tuthill", "given_name": "Peter", "orcid": "0000-0001-7026-6291" }, { "family_name": "Weigelt", "given_name": "Gerd", "orcid": "0000-0001-9754-2233" }, { "family_name": "Williams", "given_name": "Peredur M.", "orcid": "0000-0002-8092-980X" }, { "family_name": "Yamaguchi", "given_name": "Ryodai" } ], "abstract": "Massive colliding-wind binaries that host a Wolf\u2013Rayet (WR) star present a potentially important source of dust and chemical enrichment in the interstellar medium. However, the chemical composition and survival of dust formed from such systems is not well understood. The carbon-rich Wolf\u2013Rayet binary WR 140 presents an ideal astrophysical laboratory for investigating these questions, given its well-defined orbital period and predictable dust-formation episodes every 7.93\u2009years around periastron passage. We present observations from our Early Release Science programme (ERS 1349) with the James Webb Space Telescope Mid-Infrared Instrument (MIRI) Medium-Resolution Spectrometer and Imager that reveal the spectral and spatial signatures of nested circumstellar dust shells around WR 140. MIRI medium-resolution spectroscopy of the second dust shell and Imager detections of over 17 shells formed throughout approximately the past 130\u2009years confirm the survival of carbonaceous dust grains from WR 140 that are probably carriers of 'unidentified infrared'-band features at 6.4 and 7.7\u2009\u03bcm. The observations indicate that dust-forming carbon-rich Wolf\u2013Rayet binaries can enrich the interstellar medium with organic compounds and carbonaceous dust.", "doi": "10.1038/s41550-022-01812-x", "issn": "2397-3366", "publisher": "Nature Publishing Group", "publication": "Nature Astronomy", "publication_date": "2022-11", "series_number": "11", "volume": "6", "issue": "11", "pages": "1308-1316" }, { "id": "authors:1azpx-42142", "collection": "authors", "collection_id": "1azpx-42142", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220526-173308925", "type": "article", "title": "SRGA J181414.6-225604: A New Galactic Symbiotic X-Ray Binary Outburst Triggered by an Intense Mass-loss Episode of a Heavily Obscured Mira Variable", "author": [ { "family_name": "De", "given_name": "Kishalay", "orcid": "0000-0002-8989-0542", "clpid": "De-Kishalay" }, { "family_name": "Mereminskiy", "given_name": "Ilya", "orcid": "0000-0001-8931-1320", "clpid": "Mereminskiy-Ilya-A" }, { "family_name": "Soria", "given_name": "Roberto", "orcid": "0000-0002-4622-796X", "clpid": "Soria-Roberto" }, { "family_name": "Conroy", "given_name": "Charlie", "orcid": "0000-0002-1590-8551", "clpid": "Conroy-Charlie" }, { "family_name": "Kara", "given_name": "Erin", "orcid": "0000-0003-0172-0854", "clpid": "Kara-Erin" }, { "family_name": "Anand", "given_name": "Shreya", "orcid": "0000-0003-3768-7515", "clpid": "Anand-Shreya-G" }, { "family_name": "Ashley", "given_name": "Michael C. B.", "orcid": "0000-0003-1412-2028", "clpid": "Ashley-Michael-C-B" }, { "family_name": "Boyer", "given_name": "Martha L.", "orcid": "0000-0003-4850-9589", "clpid": "Boyer-Martha-L" }, { "family_name": "Chakrabarty", "given_name": "Deepto", "orcid": "0000-0001-8804-8946", "clpid": "Chakrabarty-Deepto" }, { "family_name": "Grefenstette", "given_name": "Brian", "orcid": "0000-0002-1984-2932", "clpid": "Grefenstette-Brian-W" }, { "family_name": "Hankins", "given_name": "Matthew J.", "orcid": "0000-0001-9315-8437", "clpid": "Hankins-Matthew-J" }, { "family_name": "Hillenbrand", "given_name": "Lynne A.", "clpid": "Hillenbrand-L-A" }, { "family_name": "Jencson", "given_name": "Jacob E.", "orcid": "0000-0001-5754-4007", "clpid": "Jencson-Jacob-E" }, { "family_name": "Karambelkar", "given_name": "Viraj", "orcid": "0000-0003-2758-159X", "clpid": "Karambelkar-Viraj-R" }, { "family_name": "Kasliwal", "given_name": "Mansi M.", "orcid": "0000-0002-5619-4938", "clpid": "Kasliwal-M-M" }, { "family_name": "Lau", "given_name": "Ryan M.", "orcid": "0000-0003-0778-0321", "clpid": "Lau-Ryan-M" }, { "family_name": "Lutovinov", "given_name": "Alexander", "orcid": "0000-0002-6255-9972", "clpid": "Lutovinov-Alexander-A" }, { "family_name": "Moore", "given_name": "Anna M.", "orcid": "0000-0002-2894-6936", "clpid": "Moore-Anna-M" }, { "family_name": "Ng", "given_name": "Mason", "orcid": "0000-0002-0940-6563", "clpid": "Ng-Mason" }, { "family_name": "Panagiotou", "given_name": "Christos", "clpid": "Panagiotou-Christos" }, { "family_name": "Pasham", "given_name": "Dheeraj R.", "orcid": "0000-0003-1386-7861", "clpid": "Pasham-Dheeraj-R" }, { "family_name": "Semena", "given_name": "Andrey", "clpid": "Semena-Andrey-N" }, { "family_name": "Simcoe", "given_name": "Robert", "orcid": "0000-0003-3769-9559", "clpid": "Simcoe-Robert-A" }, { "family_name": "Soon", "given_name": "Jamie", "clpid": "Soon-Jamie" }, { "family_name": "Srinivasaragavan", "given_name": "Gokul P.", "clpid": "Srinivasaragavan-Gokul-P" }, { "family_name": "Travouillon", "given_name": "Tony", "orcid": "0000-0002-7279-3658", "clpid": "Travouillon-Tony-D" }, { "family_name": "Yao", "given_name": "Yuhan", "orcid": "0000-0001-6747-8509", "clpid": "Yao-Yuhan" } ], "abstract": "We present the discovery and multiwavelength characterization of SRGA J181414.6-225604, a Galactic hard X-ray transient discovered during the ongoing SRG/ART-XC sky survey. Using data from the Palomar Gattini-IR survey, we identify a spatially and temporally coincident variable infrared (IR) source, IRAS 18111-2257, and classify it as a very-late-type (M7\u2013M8), long-period (1502 \u00b1 24 days), and luminous (M_K \u2248 \u22129.9 \u00b1 0.2) O-rich Mira donor star located at a distance of \u224814.6^(+2.9)_(\u22122.3) kpc. Combining multicolor photometric data over the last \u224825 yr, we show that the IR counterpart underwent a recent (starting \u2248800 days before the X-ray flare) enhanced mass-loss (reaching \u22482.1 \u00d7 10\u207b\u2075 M_\u2299 yr\u207b\u00b9) episode, resulting in an expanding dust shell obscuring the underlying star. Multi-epoch follow-up observations from Swift, NICER, and NuSTAR reveal a \u2248200 day long X-ray outburst reaching a peak luminosity of L_\u2093 \u2248 2.5 \u00d7 10\u00b3\u2076 erg s\u207b\u00b9, characterized by a heavily absorbed (N_H \u2248 6 \u00d7 10\u00b2\u00b2 cm\u207b\u00b2) X-ray spectrum consistent with an optically thick Comptonized plasma. The X-ray spectral and timing behavior suggest the presence of clumpy wind accretion, together with a dense ionized nebula overabundant in silicate material surrounding the compact object. Together, we show that SRGA J181414.6-225604 is a new symbiotic X-ray binary in outburst, triggered by an intense dust-formation episode of a highly evolved donor. Our results offer the first direct confirmation for the speculated connection between enhanced late-stage donor mass loss and the active lifetimes of symbiotic X-ray binaries.", "doi": "10.3847/1538-4357/ac7c6e", "issn": "0004-637X", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal", "publication_date": "2022-08-10", "series_number": "1", "volume": "935", "issue": "1", "pages": "Art. No. 36" }, { "id": "authors:q0bbr-ze020", "collection": "authors", "collection_id": "q0bbr-ze020", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20211213-225024102", "type": "article", "title": "PGIR 20eid (SN 2020qmp): A Type IIP Supernova at 15.6 Mpc discovered by the Palomar Gattini-IR survey", "author": [ { "family_name": "Srinivasaragavan", "given_name": "G. P.", "clpid": "Srinivasaragavan-G-P" }, { "family_name": "Sfaradi", "given_name": "I.", "clpid": "Sfaradi-Itai" }, { "family_name": "Jencson", "given_name": "J.", "orcid": "0000-0001-5754-4007", "clpid": "Jencson-Jacob-E" }, { "family_name": "De", "given_name": "K.", "orcid": "0000-0002-8989-0542", "clpid": "De-Kishalay" }, { "family_name": "Horesh", "given_name": "A.", "orcid": "0000-0002-5936-1156", "clpid": "Horesh-Assaf" }, { "family_name": "Kasliwal", "given_name": "M. M.", "orcid": "0000-0002-5619-4938", "clpid": "Kasliwal-M-M" }, { "family_name": "Tinyanont", "given_name": "S.", "orcid": "0000-0002-1481-4676", "clpid": "Tinyanont-Samaporn" }, { "family_name": "Hankins", "given_name": "M.", "orcid": "0000-0001-9315-8437", "clpid": "Hankins-Matthew-J" }, { "family_name": "Schulze", "given_name": "S.", "orcid": "0000-0001-6797-1889", "clpid": "Schulze-Steve" }, { "family_name": "Ashley", "given_name": "M. C. B.", "orcid": "0000-0003-1412-2028", "clpid": "Ashley-Michael-C-B" }, { "family_name": "Graham", "given_name": "M. J.", "orcid": "0000-0002-3168-0139", "clpid": "Graham-M-J" }, { "family_name": "Karambelkar", "given_name": "V.", "orcid": "0000-0003-2758-159X", "clpid": "Karambelkar-Viraj-R" }, { "family_name": "Lau", "given_name": "R.", "clpid": "Lau-Ryan-M" }, { "family_name": "Mahabal", "given_name": "A. A.", "orcid": "0000-0003-2242-0244", "clpid": "Mahabal-Ashish-A" }, { "family_name": "Moore", "given_name": "A. M.", "orcid": "0000-0002-2894-6936", "clpid": "Moore-Anna-Marie" }, { "family_name": "Ofek", "given_name": "E. O.", "orcid": "0000-0002-6786-8774", "clpid": "Ofek-Eran-O" }, { "family_name": "Sharma", "given_name": "Y.", "orcid": "0000-0003-4531-1745", "clpid": "Sharma-Yashvi" }, { "family_name": "Sollerman", "given_name": "J.", "orcid": "0000-0003-1546-6615", "clpid": "Sollerman-Jesper" }, { "family_name": "Soon", "given_name": "J.", "clpid": "Soon-Jamie" }, { "family_name": "Soria", "given_name": "R.", "orcid": "0000-0002-4622-796X", "clpid": "Soria-Roberto" }, { "family_name": "Travouillon", "given_name": "T.", "orcid": "0000-0001-9304-6718", "clpid": "Travouillon-Tony-D" }, { "family_name": "Walters", "given_name": "R.", "orcid": "0000-0002-1835-6078", "clpid": "Walters-Richard-S" } ], "abstract": "Aims. We present a detailed analysis of SN 2020qmp, a nearby Type IIP core-collapse supernova (CCSN) that was discovered by the Palomar Gattini-IR survey in the galaxy UGC07125 (distance of \u224815.6 \u00b1 4 Mpc). We illustrate how the multiwavelength study of this event helps our general understanding of stellar progenitors and circumstellar medium (CSM) interactions in CCSNe. We highlight the importance of near-infrared (NIR) surveys for detections of supernovae in dusty environments.\nMethods. We analyze data from observations in various bands: radio, NIR, optical, and X-rays. We use optical and NIR data for a spectroscopic and spectro-polarimetric study of the supernova and to model its light curve (LC). We obtain an estimate of the zero-age main-sequence (ZAMS) progenitor mass from the luminosity of the [O\u202fI] doublet lines (\u03bb\u03bb6300,\u20066364) normalized to the decay power of \u2075\u2076Co. We also independently estimate the explosion energy and ZAMS progenitor mass through hydrodynamical LC modeling. From radio and X-ray observations, we derive the mass-loss rate and microphysical parameters of the progenitor star, and we investigate possible deviations from energy equipartition of magnetic fields and electrons in a standard CSM interaction model. Finally, we simulate a sample of CCSNe with plausible distributions of brightness and extinction, within 40 Mpc, and test what fraction of the sample is detectable at peak light by NIR surveys versus optical surveys.\nResults. SN 2020qmp displays characteristic hydrogen lines in its optical spectra as well as a plateau in its optical LC, hallmarks of a Type IIP supernova. We do not detect linear polarization during the plateau phase, with a 3\u03c3 upper limit of 0.78%. Through hydrodynamical LC modeling and an analysis of its nebular spectra, we estimate a ZAMS progenitor mass of around 11.0 M\u2299 and an explosion energy of around 0.8 \u00d7 10\u2075\u00b9 erg. We find that the spectral energy distribution cannot be explained by a simple CSM interaction model, assuming a constant shock velocity and a steady mass-loss rate. In particular, the excess X-ray luminosity compared with the synchrotron radio luminosity suggests deviations from equipartition. Finally, we demonstrate the advantages of NIR surveys over optical surveys for the detection of dust-obscured CCSNe in the local Universe. Specifically, our simulations show that the Wide-Field Infrared Transient Explorer will detect up to 14 more CCSNe (out of the 75 expected in its footprint) within 40 Mpc over five years than would an optical survey equivalent to the Zwicky Transient Facility.\nConclusions. We have determined or constrained the main properties of SN 2020qmp and its progenitor, highlighting the value of multiwavelength follow-up observations of nearby CCSNe. We have shown that forthcoming NIR surveys will enable us to improve constraints on the local CCSN rate by detecting obscured supernovae that would be missed by optical searches.", "doi": "10.1051/0004-6361/202142158", "issn": "0004-6361", "publisher": "EDP Sciences", "publication": "Astronomy and Astrophysics", "publication_date": "2022-04", "volume": "660", "pages": "Art. No. A138" }, { "id": "authors:5r85g-ac787", "collection": "authors", "collection_id": "5r85g-ac787", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220224-200914705", "type": "article", "title": "A Massive AGB Donor in Scutum X-1: Identification of the First Mira Variable in an X-Ray Binary", "author": [ { "family_name": "De", "given_name": "Kishalay", "orcid": "0000-0002-8989-0542", "clpid": "De-Kishalay" }, { "family_name": "Chakrabarty", "given_name": "Deepto", "orcid": "0000-0001-8804-8946", "clpid": "Chakrabarty-Deepto" }, { "family_name": "Soria", "given_name": "Roberto", "orcid": "0000-0002-4622-796X", "clpid": "Soria-Roberto" }, { "family_name": "Ashley", "given_name": "Michael C. B.", "orcid": "0000-0003-1412-2028", "clpid": "Ashley-Michael-C-B" }, { "family_name": "Conroy", "given_name": "Charlie", "orcid": "0000-0002-1590-8551", "clpid": "Conroy-Charlie" }, { "family_name": "Hankins", "given_name": "Matthew J.", "orcid": "0000-0001-9315-8437", "clpid": "Hankins-Matthew-J" }, { "family_name": "Kasliwal", "given_name": "Mansi M.", "orcid": "0000-0002-5619-4938", "clpid": "Kasliwal-M-M" }, { "family_name": "Lau", "given_name": "Ryan M.", "clpid": "Lau-Ryan-M" }, { "family_name": "Moore", "given_name": "Anna M.", "orcid": "0000-0002-2894-6936", "clpid": "Moore-Anna-M" }, { "family_name": "Simcoe", "given_name": "Robert", "orcid": "0000-0003-3769-9559", "clpid": "Simcoe-Robert-A" }, { "family_name": "Soon", "given_name": "Jamie", "clpid": "Soon-Jamie" }, { "family_name": "Travouillon", "given_name": "Tony", "orcid": "0000-0002-7279-3658", "clpid": "Travouillon-Tony-D" } ], "abstract": "The symbiotic X-ray binary Sct X-1 was suggested to be the first known neutron star accreting from a red supergiant companion. Although known for nearly 50 yr, detailed characterization of the donor remains lacking, particularly due to the extremely high reddening toward the source (A_V \u2273 25 mag). Here, we present (i) improved localization of the counterpart using Gaia and Chandra observations, (ii) the first broadband infrared spectrum (\u22481\u20135 \u03bcm; R \u2248 2000) obtained with SpeX on the NASA Infrared Telescope Facility, and (iii) the J-band light curve from the Palomar Gattini-IR survey. The infrared spectrum is characterized by (i) deep water absorption features (H\u2082O index \u2248 40%), (ii) strong TiO, VO, and CO features, and (iii) weak/absent CN lines. We show that these features are inconsistent with known red supergiants but suggest an M8-9 III\u2013type O-rich Mira donor star. We report the discovery of large-amplitude (\u0394J \u2248 3.5 mag) periodic photometric variability, suggesting a pulsation period of 621 \u00b1 36 (systematic) \u00b1 8 (statistical) days, which we use to constrain the donor to be a relatively luminous Mira (M_K = \u22128.6 \u00b1 0.3 mag) at a distance of 3.6^(+0.8)_(\u22120.7) kpc. Comparing these characteristics to recent models, we find the donor to be consistent with a \u22483\u20135 M\u2299 star at an age of \u22480.1\u20130.3 Gyr. Together, we show that Sct X-1 was previously misclassified as an evolved high-mass X-ray binary; instead, it is an intermediate-mass system with the first confirmed Mira donor in an X-ray binary. We discuss the implications of Mira donors in symbiotic X-ray binaries and highlight the potential of wide-field infrared time-domain surveys and broadband infrared spectroscopy to unveil their demographics.", "doi": "10.3847/2041-8213/ac5b11", "issn": "2041-8205", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal Letters", "publication_date": "2022-03-20", "series_number": "1", "volume": "928", "issue": "1", "pages": "Art. No. L8" }, { "id": "authors:45d0c-t2v50", "collection": "authors", "collection_id": "45d0c-t2v50", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190614-134342384", "type": "article", "title": "Spitzer mid-infrared detections of neutron star merger GW170817 suggests synthesis of the heaviest elements", "author": [ { "family_name": "Kasliwal", "given_name": "Mansi M.", "orcid": "0000-0002-5619-4938", "clpid": "Kasliwal-M-M" }, { "family_name": "Kasen", "given_name": "Daniel", "clpid": "Kasen-Daniel" }, { "family_name": "Lau", "given_name": "Ryan M.", "clpid": "Lau-Ryan-M" }, { "family_name": "Perley", "given_name": "Daniel A.", "orcid": "0000-0001-8472-1996", "clpid": "Perley-Daniel-A" }, { "family_name": "Rosswog", "given_name": "Stephan", "clpid": "Rosswog-Stephan" }, { "family_name": "Ofek", "given_name": "Eran O.", "orcid": "0000-0002-6786-8774", "clpid": "Ofek-Eran-O" }, { "family_name": "Hotokezaka", "given_name": "Kenta", "orcid": "0000-0002-2502-3730", "clpid": "Hotokezaka-Kenta" }, { "family_name": "Chary", "given_name": "Ranga-Ram", "orcid": "0000-0001-7583-0621", "clpid": "Chary-Ranga-Ram" }, { "family_name": "Sollerman", "given_name": "Jesper", "orcid": "0000-0003-1546-6615", "clpid": "Sollerman-Jesper" }, { "family_name": "Goobar", "given_name": "Ariel", "orcid": "0000-0002-4163-4996", "clpid": "Goobar-Ariel" }, { "family_name": "Kaplan", "given_name": "David L.", "orcid": "0000-0001-6295-2881", "clpid": "Kaplan-David-L" } ], "abstract": "We report our Spitzer Space Telescope observations and detections of the binary neutron star merger GW170817. At 4.5 \u03bcm, GW170817 is detected at 21.9 \u2009mag AB at +43\u2009days and 23.9\u2009mag AB at +74\u2009days after merger. At 3.6 \u03bcm, GW170817 is not detected to a limit of 23.2\u2009mag AB at +43\u2009days and 23.1\u2009mag AB at +74\u2009days. Our detections constitute the latest and reddest constraints on the kilonova/macronova emission and composition of heavy elements. The 4.5 \u03bcm luminosity at this late phase cannot be explained by elements exclusively from the first abundance peak of the r-process. Moreover, the steep decline in the Spitzer band, with a power-law index of 3.4 \u00b1 0.2, can be explained by a few of the heaviest isotopes with half-life around 14 \u2009d dominating the luminosity (e.g. \u00b9\u2074\u2070Ba, \u00b9\u2074\u00b3Pr, \u00b9\u2074\u2077Nd, \u00b9\u2075\u2076Eu, \u00b9\u2079\u00b9Os, \u00b2\u00b2\u00b3Ra, \u00b2\u00b2\u2075Ra, \u00b2\u00b3\u00b3Pa, \u00b2\u00b3\u2074Th) or a model with lower deposition efficiency. This data offers evidence that the heaviest elements in the second and third r-process abundance peak were indeed synthesized. Our conclusion is verified by both analytics and network simulations and robust despite intricacies and uncertainties in the nuclear physics. Future observations with Spitzer and James Webb Space Telescope will further illuminate the relative abundance of the synthesized heavy elements.", "doi": "10.1093/mnrasl/slz007", "issn": "1745-3925", "publisher": "Royal Astronomical Society", "publication": "Monthly Notices of the Royal Astronomical Society: Letters", "publication_date": "2022-02", "series_number": "1", "volume": "510", "issue": "1", "pages": "L7-L12" }, { "id": "authors:hb93a-6rh81", "collection": "authors", "collection_id": "hb93a-6rh81", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210318-154128565", "type": "article", "title": "Discovery of a 310 Day Period from the Enshrouded Massive System NaSt1 (WR 122)", "author": [ { "family_name": "Lau", "given_name": "Ryan M.", "clpid": "Lau-Ryan-M" }, { "family_name": "Tinyanont", "given_name": "Samaporn", "orcid": "0000-0002-1481-4676", "clpid": "Tinyanont-Samaporn" }, { "family_name": "Hankins", "given_name": "Matthew J.", "orcid": "0000-0001-9315-8437", "clpid": "Hankins-Matthew-J" }, { "family_name": "Ashley", "given_name": "Michael C. B.", "orcid": "0000-0003-1412-2028", "clpid": "Ashley-Michael-C-B" }, { "family_name": "De", "given_name": "Kishalay", "orcid": "0000-0002-8989-0542", "clpid": "De-Kishalay" }, { "family_name": "Filippenko", "given_name": "Alexei V.", "orcid": "0000-0003-3460-0103", "clpid": "Filippenko-Alexei-V" }, { "family_name": "Hillenbrand", "given_name": "Lynne A.", "clpid": "Hillenbrand-L-A" }, { "family_name": "Kasliwal", "given_name": "Mansi M.", "orcid": "0000-0002-5619-4938", "clpid": "Kasliwal-M-M" }, { "family_name": "Mauerhan", "given_name": "Jon C.", "orcid": "0000-0002-7555-8741", "clpid": "Mauerhan-Jon-C" }, { "family_name": "Moffat", "given_name": "Anthony F. J.", "orcid": "0000-0002-4333-9755", "clpid": "Moffat-Anthony-F-J" }, { "family_name": "Moore", "given_name": "Anna M.", "orcid": "0000-0002-2894-6936", "clpid": "Moore-Anna-M" }, { "family_name": "Smith", "given_name": "Nathan", "orcid": "0000-0001-5510-2424", "clpid": "Smith-Nathan" }, { "family_name": "Soon", "given_name": "Jamie", "clpid": "Soon-Jamie" }, { "family_name": "Soria", "given_name": "Roberto", "orcid": "0000-0002-4622-796X", "clpid": "Soria-Roberto" }, { "family_name": "Travouillon", "given_name": "Tony", "orcid": "0000-0001-9304-6718", "clpid": "Travouillon-Tony-D" }, { "family_name": "van der Hucht", "given_name": "Karel A.", "clpid": "van-der-Hucht-Karel-A" }, { "family_name": "Williams", "given_name": "Peredur M.", "orcid": "0000-0002-8092-980X", "clpid": "Williams-Peredur-M" }, { "family_name": "Zheng", "given_name": "WeiKang", "orcid": "0000-0002-2636-6508", "clpid": "Zheng-Weikang" } ], "abstract": "We present optical and infrared (IR) light curves of NaSt1, also known as Wolf\u2013Rayet 122, with observations from Palomar Gattini-IR (PGIR), the Zwicky Transient Facility (ZTF), the Katzman Automatic Imaging Telescope, the Asteroid Terrestrial-impact Last Alert System, and the All-Sky Automated Survey for Supernovae (ASAS-SN). We identify a P = 309.7 \u00b1 0.7 day photometric period from the optical and IR light curves that reveal periodic, sinusoidal variability between 2014 July and 2021 July. We also present historical IR light curves taken between 1983 July and 1989 May, which show variability consistent with the period of the present-day light curves. In the past, NaSt1 was brighter in the J band with larger variability amplitudes than the present-day PGIR values, suggesting that NaSt1 exhibits variability on longer (\u2273decade) timescales. Sinusoidal fits to the recent optical and IR light curves show that the amplitude of NaSt1's variability differs at various wavelengths and also reveal significant phase offsets of 17.0 \u00b1 2.5 day between the ZTF r and PGIR J light curves. We interpret the 310 day photometric period from NaSt1 as the orbital period of an enshrouded massive binary. We suggest that the photometric variability of NaSt1 may arise from variations in the line-of-sight optical depth toward circumstellar optical/IR-emitting regions throughout its orbit due to colliding-wind dust formation. We speculate that past mass transfer in NaSt1 may have been triggered by Roche-lobe overflow (RLOF) during an eruptive phase of an Ofpe/WN9 star. Lastly, we argue that NaSt1 is no longer undergoing RLOF mass transfer.", "doi": "10.3847/1538-4357/ac2237", "issn": "0004-637X", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal", "publication_date": "2021-11-20", "series_number": "1", "volume": "922", "issue": "1", "pages": "Art. No. 5" }, { "id": "authors:41ykk-v6d80", "collection": "authors", "collection_id": "41ykk-v6d80", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20211103-193256222", "type": "article", "title": "Second Timescale Photometry of the Very Fast Nova V1674 Her with Palomar Gattini-IR", "author": [ { "family_name": "Hansen", "given_name": "Kylie Y.", "orcid": "0000-0001-5894-4651", "clpid": "Hansen-Kylie-Y" }, { "family_name": "De", "given_name": "Kishalay", "orcid": "0000-0002-8989-0542", "clpid": "De-Kishalay" }, { "family_name": "Ashley", "given_name": "Michael C. B.", "orcid": "0000-0003-1412-2028", "clpid": "Ashley-Michael-C-B" }, { "family_name": "Kasliwal", "given_name": "Mansi M.", "orcid": "0000-0002-5619-4938", "clpid": "Kasliwal-M-M" }, { "family_name": "Delacroix", "given_name": "Alexander", "clpid": "Delacroix-Alexander" }, { "family_name": "Greffe", "given_name": "Tim", "clpid": "Greffe-Timoth\u00e9e" }, { "family_name": "Hale", "given_name": "David", "clpid": "Hale-David-D-S" }, { "family_name": "Hankins", "given_name": "Matthew J.", "orcid": "0000-0001-9315-8437", "clpid": "Hankins-Matthew-J" }, { "family_name": "Lau", "given_name": "Ryan", "clpid": "Lau-Ryan-M" }, { "family_name": "Li", "given_name": "Chengkui", "clpid": "Li-Chengkui" }, { "family_name": "McKenna", "given_name": "Daniel", "clpid": "McKenna-Daniel-L" }, { "family_name": "Moore", "given_name": "Anna M.", "orcid": "0000-0002-2894-6936", "clpid": "Moore-Anna-M" }, { "family_name": "Ofek", "given_name": "Eran O.", "orcid": "0000-0002-6786-8774", "clpid": "Ofek-Eran-O" }, { "family_name": "Smith", "given_name": "Roger M.", "orcid": "0000-0001-7062-9726", "clpid": "Smith-R-M" }, { "family_name": "Soon", "given_name": "Jamie", "clpid": "Soon-Jamie" }, { "family_name": "Soria", "given_name": "Roberto", "orcid": "0000-0002-4622-796X", "clpid": "Soria-Roberto" }, { "family_name": "Srinivasaragavan", "given_name": "Gokul P.", "clpid": "Srinivasaragavan-Gokul-P" }, { "family_name": "Travouillon", "given_name": "Tony", "orcid": "0000-0002-7279-3658", "clpid": "Travouillon-Tony-D" } ], "abstract": "We report second-timescale infrared photometry of the nova V1674 Her using Palomar Gattini-IR (PGIR). These observations constitute the first infrared and highest temporal resolution data (resolution of \u22480.84\u2009s) of the nova reported to date. PGIR observed in this fast readout mode for more than an hour on three nights between 3 and 6 days after discovery. We searched for periodic variability using a Lomb\u2013Scargle periodogram and did not detect anything down to a three sigma upper limit of 0.093\u2009mag. This suggests that the periodic variability detected in the nova by Patterson et al. was lower by at least a factor of about 1.65 in the first week of the eruption.", "doi": "10.3847/2515-5172/ac3256", "issn": "2515-5172", "publisher": "American Astronomical Society", "publication": "Research Notes of the AAS", "publication_date": "2021-10", "series_number": "10", "volume": "5", "issue": "10", "pages": "Art. No. 244" }, { "id": "authors:c1vk1-s4491", "collection": "authors", "collection_id": "c1vk1-s4491", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210520-145947094", "type": "article", "title": "The luminous red nova AT 2018bwo in NGC 45 and its binary yellow supergiant progenitor", "author": [ { "family_name": "Blagorodnova", "given_name": "Nadejda", "orcid": "0000-0003-0901-1606", "clpid": "Blagorodnova-Nadejda" }, { "family_name": "Klencki", "given_name": "Jakub", "orcid": "0000-0002-7527-5741", "clpid": "Klencki-Jakub" }, { "family_name": "Pejcha", "given_name": "Ondrej", "orcid": "0000-0003-2512-2170", "clpid": "Pejcha-Ondrej" }, { "family_name": "Vreeswijk", "given_name": "Paul M.", "orcid": "0000-0002-7572-9088", "clpid": "Vreeswijk-Paul-M" }, { "family_name": "Bond", "given_name": "Howard E.", "orcid": "0000-0003-1377-7145", "clpid": "Bond-Howard-E" }, { "family_name": "Burdge", "given_name": "Kevin B.", "orcid": "0000-0002-7226-836X", "clpid": "Burdge-Kevin-B" }, { "family_name": "De", "given_name": "Kishalay", "orcid": "0000-0002-8989-0542", "clpid": "De-Kishalay" }, { "family_name": "Fremling", "given_name": "Christoffer", "orcid": "0000-0002-4223-103X", "clpid": "Fremling-Christoffer" }, { "family_name": "Gehrz", "given_name": "Robert D.", "orcid": "0000-0003-1319-4089", "clpid": "Gehrz-Robert-D" }, { "family_name": "Jencson", "given_name": "Jacob E.", "orcid": "0000-0001-5754-4007", "clpid": "Jencson-Jacob-E" }, { "family_name": "Kasliwal", "given_name": "Mansi M.", "orcid": "0000-0002-5619-4938", "clpid": "Kasliwal-M-M" }, { "family_name": "Kupfer", "given_name": "Thomas", "orcid": "0000-0002-6540-1484", "clpid": "Kupfer-Thomas" }, { "family_name": "Lau", "given_name": "Ryan M.", "clpid": "Lau-Ryan-M" }, { "family_name": "Masci", "given_name": "Frank J.", "orcid": "0000-0002-8532-9395", "clpid": "Masci-Frank-J" }, { "family_name": "Rich", "given_name": "Michael R.", "orcid": "0000-0003-0427-8387", "clpid": "Rich-Michael-R" } ], "abstract": "Luminous red novae (LRNe) are astrophysical transients associated with the partial ejection of a binary system's common envelope shortly before its merger. Here we present the results of our photometric and spectroscopic follow-up campaign of AT 2018bwo (DLT 18x), a LRN discovered in NGC 45, and investigate its progenitor system using binary stellar-evolution models. The transient reached a peak magnitude of M_r\u2004=\u2004\u221210.97 \u00b1 0.11 and maintained this brightness during its optical plateau of t_p\u2004=\u200441 \u00b1 5 days. During this phase, it showed a rather stable photospheric temperature of \u223c3300 K and a luminosity of \u223c10\u2074\u2070 erg s\u207b\u00b9. Although the luminosity and duration of AT 2018bwo is comparable to the LRNe V838 Mon and M31-2015LRN, its photosphere at early times appears larger and cooler, likely due to an extended mass-loss episode before the merger. Toward the end of the plateau, optical spectra showed a reddened continuum with strong molecular absorption bands. The IR spectrum at +103 days after discovery was comparable to that of a M8.5 II type star, analogous to an extended AGB star. The reprocessed emission by the cooling dust was also detected in the mid-infrared bands \u223c1.5 years after the outburst. Archival Spitzer and Hubble Space Telescope data taken 10\u221214 yrs before the transient event suggest a progenitor star with T_(prog)\u2004\u223c\u20046500 K, R_(prog)\u2004\u223c\u2004100 R\u2299, and L_(prog)\u2004=\u20042 \u00d7 10\u2074 L\u2299, and an upper limit for optically thin warm (1000 K) dust mass of M_d\u2004<\u200410\u207b\u2076 M\u2299. Using stellar binary-evolution models, we determined the properties of binary systems consistent with the progenitor parameter space. For AT 2018bwo, we infer a primary mass of 12\u201316 M\u2299, which is 9\u201345% larger than the \u223c11 M\u2299 obtained using single-star evolution models. The system, consistent with a yellow-supergiant primary, was likely in a stable mass-transfer regime with \u22122.4 \u2264 log(\u1e40/M\u2299 yr\u207b\u00b9) \u2264 \u22121.2 a decade before the main instability occurred. During the dynamical merger, the system would have ejected 0.15\u20130.5 M\u2299 with a velocity of \u223c500 km s\u207b\u00b9.", "doi": "10.1051/0004-6361/202140525", "issn": "0004-6361", "publisher": "EDP Sciences", "publication": "Astronomy and Astrophysics", "publication_date": "2021-09", "volume": "653", "pages": "Art. No. A134" }, { "id": "authors:pw1ds-x7206", "collection": "authors", "collection_id": "pw1ds-x7206", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210204-092712042", "type": "article", "title": "A Population of Heavily Reddened, Optically Missed Novae from Palomar Gattini-IR: Constraints on the Galactic Nova Rate", "author": [ { "family_name": "De", "given_name": "Kishalay", "orcid": "0000-0002-8989-0542", "clpid": "De-Kishalay" }, { "family_name": "Kasliwal", "given_name": "Mansi M.", "orcid": "0000-0002-5619-4938", "clpid": "Kasliwal-M-M" }, { "family_name": "Hankins", "given_name": "Matthew J.", "orcid": "0000-0001-9315-8437", "clpid": "Hankins-Matthew-J" }, { "family_name": "Sokoloski", "given_name": "Jennifer L.", "orcid": "0000-0003-2835-0304", "clpid": "Sokoloski-Jennifer-L" }, { "family_name": "Adams", "given_name": "Scott M.", "orcid": "0000-0001-5855-5939", "clpid": "Adams-Scott-M" }, { "family_name": "Ashley", "given_name": "Michael C. B.", "orcid": "0000-0003-1412-2028", "clpid": "Ashley-Michael-C-B" }, { "family_name": "Babul", "given_name": "Aliya-Nur", "orcid": "0000-0001-5491-5423", "clpid": "Babul-Aliya-Nur" }, { "family_name": "Bagdasaryan", "given_name": "Ashot", "clpid": "Bagdasaryan-Ashot" }, { "family_name": "Delacroix", "given_name": "Alexandre", "clpid": "Delacroix-Alexandre" }, { "family_name": "Dekany", "given_name": "Richard", "orcid": "0000-0002-5884-7867", "clpid": "Dekany-Richard-G" }, { "family_name": "Greffe", "given_name": "Timoth\u00e9e", "clpid": "Greffe-Timoth\u00e9e" }, { "family_name": "Hale", "given_name": "David", "clpid": "Hale-David-D-S" }, { "family_name": "Jencson", "given_name": "Jacob E.", "orcid": "0000-0001-5754-4007", "clpid": "Jencson-Jacob-E" }, { "family_name": "Karambelkar", "given_name": "Viraj R.", "orcid": "0000-0003-2758-159X", "clpid": "Karambelkar-Viraj-R" }, { "family_name": "Lau", "given_name": "Ryan M.", "clpid": "Lau-Ryan-M" }, { "family_name": "Mahabal", "given_name": "Ashish", "orcid": "0000-0003-2242-0244", "clpid": "Mahabal-Ashish-A" }, { "family_name": "McKenna", "given_name": "Daniel", "clpid": "McKenna-Daniel-L" }, { "family_name": "Moore", "given_name": "Anna M.", "orcid": "0000-0002-2894-6936", "clpid": "Moore-Anna-M" }, { "family_name": "Ofek", "given_name": "Eran O.", "orcid": "0000-0002-6786-8774", "clpid": "Ofek-Eran-O" }, { "family_name": "Sharma", "given_name": "Manasi", "clpid": "Sharma-Manasi" }, { "family_name": "Smith", "given_name": "Roger M.", "orcid": "0000-0001-7062-9726", "clpid": "Smith-R-M" }, { "family_name": "Soon", "given_name": "Jamie", "clpid": "Soon-Jamie" }, { "family_name": "Soria", "given_name": "Roberto", "orcid": "0000-0002-4622-796X", "clpid": "Soria-Roberto" }, { "family_name": "Srinivasaragavan", "given_name": "Gokul", "clpid": "Srinivasaragavan-Gokul-P" }, { "family_name": "Tinyanont", "given_name": "Samaporn", "orcid": "0000-0002-1481-4676", "clpid": "Tinyanont-Samaporn" }, { "family_name": "Travouillon", "given_name": "Tony D.", "orcid": "0000-0001-9304-6718", "clpid": "Travouillon-Tony-D" }, { "family_name": "Tzanidakis", "given_name": "Anastasios", "orcid": "0000-0003-0484-3331", "clpid": "Tzanidakis-Anastasios" }, { "family_name": "Yao", "given_name": "Yuhan", "orcid": "0000-0001-6747-8509", "clpid": "Yao-Yuhan" } ], "abstract": "The nova rate in the Milky Way remains largely uncertain, despite its vital importance in constraining models of Galactic chemical evolution as well as understanding progenitor channels for Type Ia supernovae. The rate has been previously estimated to be in the range of \u224810\u2013300 yr\u207b\u00b9, either based on extrapolations from a handful of very bright optical novae or the nova rates in nearby galaxies; both methods are subject to debatable assumptions. The total discovery rate of optical novae remains much smaller (\u22485\u201310 yr\u207b\u00b9) than these estimates, even with the advent of all-sky optical time-domain surveys. Here, we present a systematic sample of 12 spectroscopically confirmed Galactic novae detected in the first 17 months of Palomar Gattini-IR (PGIR), a wide-field near-infrared time-domain survey. Operating in the J band (\u22481.2 \u03bcm), which is significantly less affected by dust extinction compared to optical bands, the extinction distribution of the PGIR sample is highly skewed to a large extinction values (>50% of events obscured by A_V \u2273 5 mag). Using recent estimates for the distribution of Galactic mass and dust, we show that the extinction distribution of the PGIR sample is commensurate with dust models. The PGIR extinction distribution is inconsistent with that reported in previous optical searches (null-hypothesis probability <0.01%), suggesting that a large population of highly obscured novae have been systematically missed in previous optical searches. We perform the first quantitative simulation of a 3\u03c0 time-domain survey to estimate the Galactic nova rate using PGIR, and derive a rate of \u224843.7^(+19.5)_(-8.7) yr\u207b\u00b9. Our results suggest that all-sky near-infrared time-domain surveys are well poised to uncover the Galactic nova population.", "doi": "10.3847/1538-4357/abeb75", "issn": "1538-4357", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal", "publication_date": "2021-05-01", "series_number": "1", "volume": "912", "issue": "1", "pages": "Art. No. 19" }, { "id": "authors:rr6w3-xab83", "collection": "authors", "collection_id": "rr6w3-xab83", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210204-092654941", "type": "article", "title": "Outbursting Young Stellar Object PGIR 20dci in the Perseus Arm", "author": [ { "family_name": "Hillenbrand", "given_name": "Lynne A.", "clpid": "Hillenbrand-L-A" }, { "family_name": "De", "given_name": "Kishalay", "orcid": "0000-0002-8989-0542", "clpid": "De-Kishalay" }, { "family_name": "Hankins", "given_name": "Matthew", "orcid": "0000-0001-9315-8437", "clpid": "Hankins-Matthew-J" }, { "family_name": "Kasliwal", "given_name": "Mansi M.", "orcid": "0000-0002-5619-4938", "clpid": "Kasliwal-M-M" }, { "family_name": "Rebull", "given_name": "Luisa M.", "orcid": "0000-0001-6381-515X", "clpid": "Rebull-Luisa-M" }, { "family_name": "Lau", "given_name": "Ryan M.", "clpid": "Lau-Ryan-M" }, { "family_name": "Cutri", "given_name": "Roc M.", "orcid": "0000-0002-0077-2305", "clpid": "Cutri-Roc-M" }, { "family_name": "Ashley", "given_name": "Michael C. B.", "orcid": "0000-0003-1412-2028", "clpid": "Ashley-Michael-C-B" }, { "family_name": "Karambelkar", "given_name": "Viraj R.", "orcid": "0000-0003-2758-159X", "clpid": "Karambelkar-Viraj-R" }, { "family_name": "Moore", "given_name": "Anna M.", "orcid": "0000-0002-2894-6936", "clpid": "Moore-Anna-M" }, { "family_name": "Travouillon", "given_name": "T.", "orcid": "0000-0001-9304-6718", "clpid": "Travouillon-Tony-D" }, { "family_name": "Mainzer", "given_name": "A. K.", "clpid": "Mainzer-Amy-K" } ], "abstract": "We report the discovery of a likely outbursting Class I young stellar object, associated with the star-forming region NGC 281-W (distance ~2.8 kpc). The source is currently seen only at infrared wavelengths, appearing in both the Palomar Gattini InfraRed (1.2 \u03bcm) and the Near-Earth Object Wide-field Infrared Survey Explorer (3.4 and 4.6 \u03bcm) photometric time-domain surveys. Recent near-infrared imaging reveals a new, extended scattered light nebula. Recent near-infrared spectroscopy confirms the similarity of PGIR 20dci to FU Ori\u2013type sources, based on strong molecular absorption in CO, H\u2082O, and OH; weak absorption in several atomic lines; and a warm wind/outflow as indicated by a P Cygni profile in the He I \u03bb10830 line. This is a rare case of an FU Ori star with a well-measured long-term photometric rise before a sharper outburst, and the second instance of an FU Ori star with a documented two-step brightening in the mid-infrared.", "doi": "10.3847/1538-3881/abe406", "issn": "1538-3881", "publisher": "American Astronomical Society", "publication": "Astronomical Journal", "publication_date": "2021-05", "series_number": "5", "volume": "161", "issue": "5", "pages": "Art. No. 220" }, { "id": "authors:dry87-kc931", "collection": "authors", "collection_id": "dry87-kc931", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210204-092715488", "type": "article", "title": "Census of R Coronae Borealis Stars. I. Infrared Light Curves from Palomar Gattini IR", "author": [ { "family_name": "Karambelkar", "given_name": "Viraj R.", "orcid": "0000-0003-2758-159X", "clpid": "Karambelkar-Viraj-R" }, { "family_name": "Kasliwal", "given_name": "Mansi M.", "orcid": "0000-0002-5619-4938", "clpid": "Kasliwal-M-M" }, { "family_name": "Tisserand", "given_name": "Patrick", "orcid": "0000-0003-4237-0520", "clpid": "Tisserand-Patrick" }, { "family_name": "De", "given_name": "Kishalay", "orcid": "0000-0002-8989-0542", "clpid": "De-Kishalay" }, { "family_name": "Anand", "given_name": "Shreya", "orcid": "0000-0003-3768-7515", "clpid": "Anand-Shreya" }, { "family_name": "Ashley", "given_name": "Michael C. B.", "orcid": "0000-0003-1412-2028", "clpid": "Ashley-Michael-C-B" }, { "family_name": "Delacroix", "given_name": "Alex", "clpid": "Delacroix-Alexandre" }, { "family_name": "Hankins", "given_name": "Matthew", "orcid": "0000-0001-9315-8437", "clpid": "Hankins-Matthew-J" }, { "family_name": "Jencson", "given_name": "Jacob E.", "orcid": "0000-0001-5754-4007", "clpid": "Jencson-Jacob-E" }, { "family_name": "Lau", "given_name": "Ryan M.", "clpid": "Lau-Ryan-M" }, { "family_name": "McKenna", "given_name": "Dan", "clpid": "McKenna-Daniel-L" }, { "family_name": "Moore", "given_name": "Anna", "orcid": "0000-0002-2894-6936", "clpid": "Moore-Anna-M" }, { "family_name": "Ofek", "given_name": "Eran O.", "orcid": "0000-0002-6786-8774", "clpid": "Ofek-Eran-O" }, { "family_name": "Smith", "given_name": "Roger M.", "orcid": "0000-0001-7062-9726", "clpid": "Smith-R-M" }, { "family_name": "Soria", "given_name": "Roberto", "orcid": "0000-0002-4622-796X", "clpid": "Soria-Roberto" }, { "family_name": "Soon", "given_name": "Jamie", "clpid": "Soon-Jamie" }, { "family_name": "Tinyanont", "given_name": "Samaporn", "orcid": "0000-0002-1481-4676", "clpid": "Tinyanont-Samaporn" }, { "family_name": "Travouillon", "given_name": "Tony", "orcid": "0000-0002-7279-3658", "clpid": "Travouillon-Tony-D" }, { "family_name": "Yao", "given_name": "Yuhan", "orcid": "0000-0001-6747-8509", "clpid": "Yao-Yuhan" } ], "abstract": "We are undertaking the first systematic infrared (IR) census of R Coronae Borealis (RCB) stars in the Milky Way, beginning with IR light curves from the Palomar Gattini IR (PGIR) survey. The PGIR is a 30 cm J-band telescope with a 25 deg\u00b2 camera that is surveying 18,000 deg\u00b2 of the northern sky (\u03b4 > \u221228\u00b0) at a cadence of 2 days. We present PGIR light curves for 922 RCB candidates selected from a mid-IR color-based catalog. Of these 922, 149 are promising RCB candidates, as they show pulsations or declines similar to RCB stars. The majority of the candidates that are not RCB stars are either long-period variables (LPVs) or RV Tauri stars. We identify IR color-based criteria to better distinguish between RCB stars and LPVs. As part of a pilot spectroscopic run, we obtain NIR spectra for 26 of the 149 promising candidates and spectroscopically confirm 11 new RCB stars. We detect strong He I \u03bb10830 features in the spectra of all RCB stars, likely originating within high-velocity (200\u2013400 km s\u207b\u00b9) winds in their atmospheres. Nine of these RCB stars show \u00b9\u00b2C\u00b9\u2076O and \u00b9\u00b2C\u00b9\u2078O molecular absorption features, suggesting that they are formed through a white dwarf merger. We detect quasiperiodic pulsations in the light curves of five RCB stars. The periods range between 30 and 125 days and likely originate from the strange-mode instability in these stars. Our pilot run results motivate a dedicated IR spectroscopic campaign to classify all RCB candidates.", "doi": "10.3847/1538-4357/abe5aa", "issn": "1538-4357", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal", "publication_date": "2021-04-01", "series_number": "2", "volume": "910", "issue": "2", "pages": "Art. No. 132" }, { "id": "authors:ywgp4-xze22", "collection": "authors", "collection_id": "ywgp4-xze22", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210204-092725706", "type": "article", "title": "Revealing Efficient Dust Formation at Low Metallicity in Extragalactic Carbon-rich Wolf-Rayet Binaries", "author": [ { "family_name": "Lau", "given_name": "Ryan M.", "clpid": "Lau-Ryan-M" }, { "family_name": "Hankins", "given_name": "Matthew J.", "orcid": "0000-0001-9315-8437", "clpid": "Hankins-Matthew-J" }, { "family_name": "Kasliwal", "given_name": "Mansi M.", "orcid": "0000-0002-5619-4938", "clpid": "Kasliwal-M-M" }, { "family_name": "Bond", "given_name": "Howard E.", "orcid": "0000-0003-1377-7145", "clpid": "Bond-Howard-E" }, { "family_name": "De", "given_name": "Kishalay", "orcid": "0000-0002-8989-0542", "clpid": "De-Kishalay" }, { "family_name": "Jencson", "given_name": "Jacob E.", "orcid": "0000-0001-5754-4007", "clpid": "Jencson-Jacob-E" }, { "family_name": "Moffat", "given_name": "Anthony F. J.", "orcid": "0000-0002-4333-9755", "clpid": "Moffat-Anthony-F-J" }, { "family_name": "Smith", "given_name": "Nathan", "orcid": "0000-0001-5510-2424", "clpid": "Smith-Nathan" }, { "family_name": "Williams", "given_name": "Peredur M.", "orcid": "0000-0002-8092-980X", "clpid": "Williams-Peredur-M" } ], "abstract": "We present Spitzer/InfraRed Array Camera observations of dust formation from six extragalactic carbon-rich Wolf-Rayet (WC) binary candidates in low-metallicity (Z \u2272 0.65 Z_\u2299) environments using multiepoch mid-infrared (IR) imaging data from the SPitzer InfraRed Intensive Transients Survey (SPIRITS). Optical follow-up spectroscopy of SPIRITS 16ln, 19q, 16df, 18hb, and 14apu reveals emission features from C IV \u03bb5801\u221212 and/or the C III\u2013IV \u03bb4650/He II \u03bb4686 blend that are consistent with early-type WC stars. We identify SPIRITS 16ln as the variable mid-IR counterpart of the recently discovered colliding-wind WC4 + O binary candidate, N604-WRXc, located in the subsolar metallicity NGC 604 H II region in M33. We interpret the mid-IR variability from SPIRITS 16ln as a dust-formation episode in an eccentric colliding-wind WC binary. SPIRITS 19q, 16df, 14apu, and 18hb exhibit absolute [3.6] magnitudes exceeding that of one of the most IR-luminous dust-forming WC systems known, WR 104 (M_([3.6]) \u2272 \u221212.3). An analysis of dust formation in the mid-IR outburst from SPIRITS 19q reveals a high dust production rate of \u1e40_d \u2273 2 \u00d7 10\u207b\u2076 M_\u2299 yr\u207b\u00b9, which may therefore exceed that of the most efficient dust-forming WC systems known. We demonstrate that efficient dust formation is feasible from early-type WC binaries in the theoretical framework of colliding-wind binary dust formation if the systems host an O-type companion with high mass-loss rates (\u1e40 \u2273 1.6 \u00d7 10\u207b\u2076 M_\u2299 yr\u207b\u00b9). This efficient dust formation from early-type WC binaries highlights their potential role as significant sources of dust in low-metallicity environments.", "doi": "10.3847/1538-4357/abd8cd", "issn": "1538-4357", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal", "publication_date": "2021-03-10", "series_number": "2", "volume": "909", "issue": "2", "pages": "Art. No. 113" }, { "id": "authors:pgd7r-sfm79", "collection": "authors", "collection_id": "pgd7r-sfm79", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200921-113043905", "type": "article", "title": "Resolving Decades of Periodic Spirals from the Wolf\u2013Rayet Dust Factory WR 112", "author": [ { "family_name": "Lau", "given_name": "Ryan M.", "clpid": "Lau-Ryan-M" }, { "family_name": "Hankins", "given_name": "Matthew J.", "orcid": "0000-0001-9315-8437", "clpid": "Hankins-M-J" }, { "family_name": "Han", "given_name": "Yinuo", "clpid": "Han-Yinuo" }, { "family_name": "Endo", "given_name": "Izumi", "clpid": "Endo-Izumi" }, { "family_name": "Moffat", "given_name": "Anthony F. J.", "clpid": "Moffat-A-F-J" }, { "family_name": "Ressler", "given_name": "Michael E.", "orcid": "0000-0001-5644-8830", "clpid": "Ressler-M-E" }, { "family_name": "Sakon", "given_name": "Itsuki", "orcid": "0000-0001-7641-5497", "clpid": "Sakon-Itsuki" }, { "family_name": "Sanchez-Bermudez", "given_name": "Joel", "orcid": "0000-0002-9723-0421", "clpid": "Sanchez-Bermudez-J" }, { "family_name": "Soulain", "given_name": "Anthony", "clpid": "Soulain-Anthony" }, { "family_name": "Stevens", "given_name": "Ian R.", "orcid": "0000-0001-7673-4340", "clpid": "Stevens-Ian-R" }, { "family_name": "Tuthill", "given_name": "Peter G.", "clpid": "Tuthill-P-G" }, { "family_name": "Williams", "given_name": "Peredur M.", "orcid": "0000-0002-8092-980X", "clpid": "Williams-P-M" } ], "abstract": "WR 112 is a dust-forming carbon-rich Wolf\u2013Rayet (WC) binary with a dusty circumstellar nebula that exhibits a complex asymmetric morphology, which traces the orbital motion and dust formation in the colliding winds of the central binary. Unraveling the complicated circumstellar dust emission around WR 112 therefore provides an opportunity to understand the dust formation process in colliding-wind WC binaries. In this work, we present a multi-epoch analysis of the circumstellar dust around WR 112 using seven high spatial resolution (FWHM ~ 0farcs3\u20130farcs4) N-band (\u03bb ~ 12 \u03bcm) imaging observations spanning almost 20 yr and that includes images obtained from Subaru/COMICS in 2019 October. In contrast to previous interpretations of a face-on spiral morphology, we observe clear evidence of proper motion of the circumstellar dust around WR 112 consistent with a nearly edge-on spiral with a \u03b8_s = 55\u00b0 half-opening angle and a ~20 yr period. The revised near edge-on geometry of WR 112 reconciles previous observations of highly variable nonthermal radio emission that was inconsistent with a face-on geometry. We estimate a revised distance to WR 112 of d = 3.39_(-0.84)^(+0.89) kpc based on the observed dust expansion rate and a spectroscopically derived WC terminal wind velocity of v_\u221e = 1230 \u00b1 260 km s\u207b\u00b9. With the newly derived WR 112 parameters, we fit optically thin dust spectral energy distribution models and determine a dust production rate of \u1e40_d = 2.7_(-1.3)^(+1.0) x 10\u207b\u2076 M_\u2299 yr\u207b\u00b9, which demonstrates that WR 112 is one of the most prolific dust-making WC systems known.", "doi": "10.3847/1538-4357/abaab8", "issn": "1538-4357", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal", "publication_date": "2020-09-10", "series_number": "2", "volume": "900", "issue": "2", "pages": "Art. No. 190" }, { "id": "authors:x0aq0-1j654", "collection": "authors", "collection_id": "x0aq0-1j654", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200724-100654391", "type": "article", "title": "Revisiting the Impact of Dust Production from Carbon-rich Wolf\u2013Rayet Binaries", "author": [ { "family_name": "Lau", "given_name": "Ryan M.", "clpid": "Lau-Ryan-M" }, { "family_name": "Eldridge", "given_name": "J. J.", "orcid": "0000-0002-1722-6343", "clpid": "Eldridge-J-J" }, { "family_name": "Hankins", "given_name": "Matthew J.", "orcid": "0000-0001-9315-8437", "clpid": "Hankins-M-J" }, { "family_name": "Lamberts", "given_name": "Astrid", "orcid": "0000-0001-8740-0127", "clpid": "Lamberts-A" }, { "family_name": "Sakon", "given_name": "Itsuki", "orcid": "0000-0001-7641-5497", "clpid": "Sakon-Itsuki" }, { "family_name": "Williams", "given_name": "Peredur M.", "orcid": "0000-0002-8092-980X", "clpid": "Williams-Peredur-M" } ], "abstract": "We present a dust spectral energy distribution (SED) and binary stellar population analysis revisiting the dust production rates (DPRs) in the winds of carbon-rich Wolf\u2013Rayet (WC) binaries and their impact on galactic dust budgets. DustEM SED models of 19 Galactic WC \"dustars\" reveal DPRs of \u1e40_d ~ 10\u207b\u00b9\u2070-10\u207b\u2076 M_\u2299 yr\u207b\u00b9 and carbon dust condensation fractions, \u03c7 C , between 0.002% and 40%. A large (0.1\u20131.0 \u03bcm) dust grain size composition is favored for efficient dustars where \u03c7_C \u2273 1%. Results for dustars with known orbital periods verify a power-law relation between \u03c7_C , orbital period, WC mass-loss rate, and wind velocity consistent with predictions from theoretical models of dust formation in colliding-wind binaries. We incorporated dust production into Binary Population and Spectral Synthesis (BPASS) models to analyze dust production rates from WC dustars, asymptotic giant branch stars (AGBs), red supergiants (RSGs), and core-collapse supernovae (SNe). BPASS models assuming constant star formation (SF) and a coeval 10\u2076 M_\u2299 stellar population were performed at low, Large Magellanic Cloud (LMC)\u2013like, and solar metallicities (Z = 0.001, 0.008, and 0.020). Both constant SF and coeval models indicate that SNe are net dust destroyers at all metallicities. Constant SF models at LMC-like metallicities show that AGB stars slightly outproduce WC binaries and RSGs by factors of 2\u20133, whereas at solar metallicities WC binaries are the dominant source of dust for ~60 Myr until the onset of AGBs, which match the dust input of WC binaries. Coeval population models show that, for \"bursty\" SF, AGB stars dominate dust production at late times (t \u2273 70 Myr).", "doi": "10.3847/1538-4357/ab9cb5", "issn": "1538-4357", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal", "publication_date": "2020-07-20", "series_number": "1", "volume": "898", "issue": "1", "pages": "Art. No. 74" }, { "id": "authors:mpzn8-syt57", "collection": "authors", "collection_id": "mpzn8-syt57", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200311-105356721", "type": "article", "title": "SOFIA/FORCAST Galactic Center Legacy Survey: Overview", "author": [ { "family_name": "Hankins", "given_name": "Matthew J.", "orcid": "0000-0001-9315-8437", "clpid": "Hankins-M-J" }, { "family_name": "Lau", "given_name": "Ryan M.", "clpid": "Lau-Ryan-M" }, { "family_name": "Radomski", "given_name": "James T.", "clpid": "Radomski-J-T" }, { "family_name": "Cotera", "given_name": "Angela S.", "clpid": "Cotera-A-S" }, { "family_name": "Morris", "given_name": "Mark R.", "orcid": "0000-0002-6753-2066", "clpid": "Morris-M-R" }, { "family_name": "Mills", "given_name": "Elisabeth A. C.", "clpid": "Mills-E-A-C" }, { "family_name": "Walker", "given_name": "Daniel L.", "clpid": "Walker-D-L" }, { "family_name": "Barnes", "given_name": "Ashley T.", "clpid": "Barnes-A-T" }, { "family_name": "Simpson", "given_name": "Janet P.", "clpid": "Simpson-J-P" }, { "family_name": "Herter", "given_name": "Terry L.", "orcid": "0000-0002-3856-8385", "clpid": "Herter-T-L" }, { "family_name": "Longmore", "given_name": "Steven N.", "clpid": "Longmore-S-N" }, { "family_name": "Bally", "given_name": "John", "orcid": "0000-0001-8135-6612", "clpid": "Bally-J" }, { "family_name": "Kasliwal", "given_name": "Mansi M.", "orcid": "0000-0002-5619-4938", "clpid": "Kasliwal-M-M" }, { "family_name": "Sabha", "given_name": "Nadeen B.", "clpid": "Sabha-N-B" }, { "family_name": "Garc\u00eda-Marin", "given_name": "Macarena", "clpid": "Garc\u00eda-Marin-M" } ], "abstract": "The Galactic Center contains some of the most extreme conditions for star formation in our Galaxy, as well as many other phenomena that are unique to this region. Given our relative proximity to the Galactic Center, we are able to study details of physical processes to a level that is simply not yet possible for more distant galaxies, yielding an otherwise inaccessible view of the nuclear region of a galaxy. We recently carried out a targeted imaging survey of mid-infrared bright portions of the Galactic Center at 25 and 37 \u03bcm using the FORCAST instrument on the Stratospheric Observatory for Infrared Astronomy (SOFIA). This survey was one of the inaugural Legacy Programs from SOFIA cycle 7, observing a total area of 403 arcmin2 (2180 pc\u00b2), including the Sgr A, B, and C complexes. Here we present an overview of the survey strategy, observations, and data reduction as an accompaniment to the initial public release of the survey data. We discuss interesting regions and features within the data, including extended features near the circumnuclear disk, structures in the Arched Filaments and Sickle H II regions, and signs of embedded star formation in Sgr B2 and Sgr C. We also feature a handful of less well studied mid-infrared sources located between Sgr A and Sgr C that could be sites of relatively isolated star formation activity. Last, we discuss plans for subsequent publications and future data releases from the survey.", "doi": "10.3847/1538-4357/ab7c5d", "issn": "1538-4357", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal", "publication_date": "2020-05-01", "series_number": "1", "volume": "894", "issue": "1", "pages": "Art. No. 55" }, { "id": "authors:p51d3-0bq11", "collection": "authors", "collection_id": "p51d3-0bq11", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200227-072944888", "type": "article", "title": "From SN 2010da to NGC 300 ULX-1: Ten Years of Observations of an Unusual High Mass X-Ray Binary in NGC 300", "author": [ { "family_name": "Binder", "given_name": "Breanna A.", "clpid": "Binder-B-A" }, { "family_name": "Carpano", "given_name": "Stefania", "clpid": "Carpano-S" }, { "family_name": "Heida", "given_name": "Marianne", "orcid": "0000-0002-1082-7496", "clpid": "Heida-M" }, { "family_name": "Lau", "given_name": "Ryan", "clpid": "Lau-Ryan-M" } ], "abstract": "In May 2010, an intermediate luminosity optical transient was discovered in the nearby galaxy NGC 300 by a South African amateur astronomer. In the decade since its discovery, multi-wavelength observations of the misnamed \"SN 2010da\" have continually reshaped our understanding of this high mass X-ray binary system. In this review, we present an overview of the multi-wavelength observations and attempt to understand the 2010 transient event, and later, the reclassification of this system as NGC 300 ULX-1: a red supergiant + neutron star ultraluminous X-ray source.", "doi": "10.3390/galaxies8010017", "issn": "2075-4434", "publisher": "MDPI", "publication": "Galaxies", "publication_date": "2020-03", "series_number": "1", "volume": "8", "issue": "1", "pages": "Art. No. 17" }, { "id": "authors:vqxva-zrd14", "collection": "authors", "collection_id": "vqxva-zrd14", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20191122-085137309", "type": "article", "title": "Palomar Gattini-IR: Survey overview, data processing system, on-sky performance and first results", "author": [ { "family_name": "De", "given_name": "Kishalay", "orcid": "0000-0002-8989-0542", "clpid": "De-Kishalay" }, { "family_name": "Hankins", "given_name": "Matthew J.", "orcid": "0000-0001-9315-8437", "clpid": "Hankins-M-J" }, { "family_name": "Kasliwal", "given_name": "Mansi M.", "orcid": "0000-0002-5619-4938", "clpid": "Kasliwal-M-M" }, { "family_name": "Moore", "given_name": "Anna M.", "orcid": "0000-0002-2894-6936", "clpid": "Moore-A-M" }, { "family_name": "Ofek", "given_name": "Eran O.", "orcid": "0000-0002-6786-8774", "clpid": "Ofek-E-O" }, { "family_name": "Adams", "given_name": "Scott M.", "orcid": "0000-0001-5855-5939", "clpid": "Adams-Scott-M" }, { "family_name": "Ashley", "given_name": "Michael C. B.", "clpid": "Ashley-M-C-B" }, { "family_name": "Babul", "given_name": "Aliya-Nur", "clpid": "Babul-A-N" }, { "family_name": "Bagdasaryan", "given_name": "Ashot", "clpid": "Bagdasaryan-A" }, { "family_name": "Burdge", "given_name": "Kevin B.", "orcid": "0000-0002-7226-836X", "clpid": "Burdge-K-B" }, { "family_name": "Burnham", "given_name": "Jill", "clpid": "Burnham-J-A" }, { "family_name": "Dekany", "given_name": "Richard G.", "clpid": "Dekany-Richard" }, { "family_name": "Declacroix", "given_name": "Alexander", "clpid": "Declacroix-A" }, { "family_name": "Galla", "given_name": "Antony", "clpid": "Galla-A" }, { "family_name": "Greffe", "given_name": "Tim", "clpid": "Greffe-T" }, { "family_name": "Hale", "given_name": "David", "clpid": "Hale-D-D-S" }, { "family_name": "Jencson", "given_name": "Jacob E.", "orcid": "0000-0001-5754-4007", "clpid": "Jencson-J-E" }, { "family_name": "Lau", "given_name": "Ryan M.", "clpid": "Lau-Ryan-M" }, { "family_name": "Mahabal", "given_name": "Ashish", "orcid": "0000-0003-2242-0244", "clpid": "Mahabal-A-A" }, { "family_name": "McKenna", "given_name": "Daniel", "clpid": "McKenna-D-L" }, { "family_name": "Sharma", "given_name": "Manasi", "clpid": "Sharma-Manasi" }, { "family_name": "Shopbell", "given_name": "Patrick L.", "clpid": "Shopbell-P-L" }, { "family_name": "Smith", "given_name": "Roger M.", "clpid": "Smith-R-M" }, { "family_name": "Soon", "given_name": "Jamie", "clpid": "Soon-Jamie" }, { "family_name": "Sokoloski", "given_name": "Jennifer", "clpid": "Sokoloski-J-L" }, { "family_name": "Soria", "given_name": "Roberto", "orcid": "0000-0002-4622-796X", "clpid": "Soria-Roberto" }, { "family_name": "Travouillon", "given_name": "Tony", "clpid": "Travouillon-T" } ], "abstract": "Palomar Gattini-IR is a new wide-field, near-infrared (NIR) robotic time domain survey operating at Palomar Observatory. Using a 30 cm telescope mounted with a H2RG detector, Gattini-IR achieves a field of view (FOV) of 25 sq. deg. with a pixel scale of 8.\"7 in J-band. Here, we describe the system design, survey operations, data processing system and on-sky performance of Palomar Gattini-IR. As a part of the nominal survey, Gattini-IR scans \u22487500 square degrees of the sky every night to a median 5\u03c3 depth of 15.7 AB mag outside the Galactic plane. The survey covers \u224815,000 square degrees of the sky visible from Palomar with a median cadence of 2 days. A real-time data processing system produces stacked science images from dithered raw images taken on sky, together with point-spread function (PSF)-fit source catalogs and transient candidates identified from subtractions within a median delay of \u22484 hr from the time of observation. The calibrated data products achieve an astrometric accuracy (rms) of \u22480.\"7 with respect to Gaia DR2 for sources with signal-to-noise ratio > 10, and better than \u22480.\"35 for sources brighter than \u224812 Vega mag. The photometric accuracy (rms) achieved in the PSF-fit source catalogs is better than \u22483% for sources brighter than \u224812 Vega mag and fainter than the saturation magnitude of \u22488.5 Vega mag, as calibrated against the Two Micron All Sky Survey catalog. The detection efficiency of transient candidates injected into the images is better than 90% for sources brighter than the 5\u03c3 limiting magnitude. The photometric recovery precision of injected sources is 3% for sources brighter than 13 mag, and the astrometric recovery rms is \u22480.\"9. Reference images generated by stacking several field visits achieve depths of \u227316.5 AB mag over 60% of the sky, while it is limited by confusion in the Galactic plane. With a FOV \u224840\u00d7 larger than any other existing NIR imaging instrument, Gattini-IR is probing the reddest and dustiest transients in the local universe such as dust obscured supernovae in nearby galaxies, novae behind large columns of extinction within the galaxy, reddened microlensing events in the Galactic plane and variability from cool and dust obscured stars. We present results from transients and variables identified since the start of the commissioning period.", "doi": "10.1088/1538-3873/ab6069", "issn": "1538-3873", "publisher": "Astronomical Society of the Pacific", "publication": "Publications of the Astronomical Society of the Pacific", "publication_date": "2020-02", "series_number": "1008", "volume": "132", "issue": "1008", "pages": "Art. No. 025001" }, { "id": "authors:x5tdx-vrg75", "collection": "authors", "collection_id": "x5tdx-vrg75", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20191002-094807190", "type": "article", "title": "Supernova 2014C: ongoing interaction with extended circumstellar material with silicate dust", "author": [ { "family_name": "Tinyanont", "given_name": "Samaporn", "orcid": "0000-0002-1481-4676", "clpid": "Tinyanont-S" }, { "family_name": "Lau", "given_name": "Ryan M.", "clpid": "Lau-Ryan-M" }, { "family_name": "Kasliwal", "given_name": "Mansi M.", "orcid": "0000-0002-5619-4938", "clpid": "Kasliwal-M-M" }, { "family_name": "Maeda", "given_name": "Keiichi", "orcid": "0000-0003-2611-7269", "clpid": "Maeda-Keiichi" }, { "family_name": "Smith", "given_name": "Nathan", "clpid": "Smith-Nathan" }, { "family_name": "Fox", "given_name": "Ori D.", "orcid": "0000-0003-2238-1572", "clpid": "Fox-O-D" }, { "family_name": "Gehrz", "given_name": "Robert D.", "orcid": "0000-0003-1319-4089", "clpid": "Gehrz-R-D" }, { "family_name": "De", "given_name": "Kishalay", "orcid": "0000-0002-8989-0542", "clpid": "De-Kishalay" }, { "family_name": "Jencson", "given_name": "Jacob", "orcid": "0000-0001-5754-4007", "clpid": "Jencson-J-E" }, { "family_name": "Bally", "given_name": "John", "orcid": "0000-0001-8135-6612", "clpid": "Bally-J" }, { "family_name": "Masci", "given_name": "Frank", "orcid": "0000-0002-8532-9395", "clpid": "Masci-F-J" } ], "abstract": "Supernova (SN) 2014C is unique: a seemingly typical hydrogen-poor SN that started to interact with a dense, hydrogen-rich circumstellar medium (CSM) ~100 days post-explosion. The delayed interaction suggests a detached CSM shell, unlike in a typical SN IIn where the CSM is much closer and the interaction commences earlier post-explosion, indicating a different mass-loss history. We present infrared observations of SN 2014C 1\u20135 yr post-explosion, including uncommon 9.7 \u03bcm imaging with COMICS on the Subaru telescope. Spectroscopy shows the intermediate-width He I 1.083 \u03bcm emission from the interacting region up to the latest epoch 1639 days post-explosion. The last Spitzer/IRAC photometry at 1920 days confirms ongoing CSM interaction. The 1\u201310 \u03bcm spectral energy distributions (SEDs) can be explained by a dust model with a mixture of 62% carbonaceous and 38% silicate dust, pointing to a chemically inhomogeneous CSM. The inference of silicate dust is the first among interacting SNe. An SED model with purely carbonaceous CSM dust, while possible, requires more than 0.22 M_\u2299 of dust, an order of magnitude larger than what has been observed in any SNe at this epoch. The light curve beyond 500 days is well fit by an interaction model with a wind-driven CSM and a mass-loss rate of ~10\u207b\u00b3 M\u2299 yr\u207b\u00b9, which presents an additional CSM density component exterior to the constant-density shell reported previously in the literature. SN 2014C could originate in a binary system, similar to RY Scuti, which would explain the observed chemical and density profile inhomogeneity in the CSM.", "doi": "10.3847/1538-4357/ab521b", "issn": "0004-637X", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal", "publication_date": "2019-12-10", "series_number": "1", "volume": "887", "issue": "1", "pages": "Art. No. 75" }, { "id": "authors:be9za-1y628", "collection": "authors", "collection_id": "be9za-1y628", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190917-093523828", "type": "article", "title": "Discovery of a red supergiant donor star in SN2010da/NGC 300 ULX-1", "author": [ { "family_name": "Heida", "given_name": "M.", "orcid": "0000-0002-1082-7496", "clpid": "Heida-M" }, { "family_name": "Lau", "given_name": "R. M.", "clpid": "Lau-Ryan-M" }, { "family_name": "Davies", "given_name": "B.", "clpid": "Davies-B" }, { "family_name": "Brightman", "given_name": "M.", "orcid": "0000-0002-8147-2602", "clpid": "Brightman-M" }, { "family_name": "F\u00fcrst", "given_name": "F.", "orcid": "0000-0003-0388-0560", "clpid": "F\u00fcrst-F" }, { "family_name": "Grefenstette", "given_name": "B. W.", "orcid": "0000-0002-1984-2932", "clpid": "Grefenstette-B-W" }, { "family_name": "Kennea", "given_name": "J. A.", "orcid": "0000-0002-6745-4790", "clpid": "Kennea-J-A" }, { "family_name": "Tramper", "given_name": "F.", "clpid": "Tramper-F" }, { "family_name": "Walton", "given_name": "D. J.", "orcid": "0000-0001-5819-3552", "clpid": "Walton-D-J" }, { "family_name": "Harrison", "given_name": "F. A.", "orcid": "0000-0002-4226-8959", "clpid": "Harrison-F-A" } ], "abstract": "SN2010da/NGC 300 ULX-1 was first detected as a supernova impostor in 2010 May and was recently discovered to be a pulsating ultraluminous X-ray source. In this Letter, we present Very Large Telescope/X-shooter spectra of this source obtained in 2018 October, covering the wavelength range 350\u20132300 nm. The J- and H-bands clearly show the presence of a red supergiant (RSG) donor star that is best matched by a MARCS stellar atmosphere with T_(eff) = 3650\u20133900 K and log(L_(bol)/L\u2299) = 4.25 \u00b1 0.10, which yields a stellar radius R = 310 \u00b1 70R \u2299. To fit the full spectrum, two additional components are required: a blue excess that can be fitted either by a hot blackbody (T \u2273 20,000 K) or a power law (spectral index \u03b1 \u2248 4) and is likely due to X-ray emission reprocessed in the outer accretion disk or the donor star; and a red excess that is well fitted by a blackbody with a temperature of ~1100 K, and is likely due to warm dust in the vicinity of SN2010da. The presence of an RSG in this system implies an orbital period of at least 0.8\u20132.1 yr, assuming Roche-lobe overflow. Given the large donor-to-compact object mass ratio, orbital modulations of the radial velocity of the RSG are likely undetectable. However, the radial velocity amplitude of the neutron star is large enough (up to 40\u201360 km s^(\u22121)) to potentially be measured in the future, unless the system is viewed at a very unfavorable inclination.", "doi": "10.3847/2041-8213/ab4139", "issn": "2041-8213", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal Letters", "publication_date": "2019-10-01", "series_number": "2", "volume": "883", "issue": "2", "pages": "Art. No. L34" }, { "id": "authors:qs3jc-2v076", "collection": "authors", "collection_id": "qs3jc-2v076", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190619-074207862", "type": "article", "title": "Discovery of an Intermediate-luminosity Red Transient in M51 and Its Likely Dust-obscured, Infrared-variable Progenitor", "author": [ { "family_name": "Jencson", "given_name": "Jacob E.", "orcid": "0000-0001-5754-4007", "clpid": "Jencson-J-E" }, { "family_name": "Adams", "given_name": "Scott M.", "orcid": "0000-0001-5855-5939", "clpid": "Adams-Scott-M" }, { "family_name": "Bond", "given_name": "Howard E.", "orcid": "0000-0003-1377-7145", "clpid": "Bond-H-E" }, { "family_name": "Van Dyk", "given_name": "Schuyler D.", "orcid": "0000-0001-9038-9950", "clpid": "Van-Dyk-S-D" }, { "family_name": "Kasliwal", "given_name": "Mansi M.", "orcid": "0000-0002-5619-4938", "clpid": "Kasliwal-M-M" }, { "family_name": "Bally", "given_name": "John", "orcid": "0000-0001-8135-6612", "clpid": "Bally-J" }, { "family_name": "Blagorodnova", "given_name": "Nadja", "orcid": "0000-0003-0901-1606", "clpid": "Blagorodnova-N" }, { "family_name": "De", "given_name": "Kishalay", "orcid": "0000-0002-8989-0542", "clpid": "De-Kishalay" }, { "family_name": "Fremling", "given_name": "Christoffer", "orcid": "0000-0002-4223-103X", "clpid": "Fremling-C" }, { "family_name": "Yao", "given_name": "Yuhan", "orcid": "0000-0001-6747-8509", "clpid": "Yao-Yuhan" }, { "family_name": "Fruchter", "given_name": "A.", "clpid": "Fruchter-A" }, { "family_name": "Rubin", "given_name": "David", "clpid": "Rubin-D" }, { "family_name": "Barbarino", "given_name": "Cristina", "orcid": "0000-0002-3821-6144", "clpid": "Barbarino-C" }, { "family_name": "Sollerman", "given_name": "J.", "orcid": "0000-0003-1546-6615", "clpid": "Sollerman-J" }, { "family_name": "Miller", "given_name": "Adam A.", "orcid": "0000-0001-9515-478X", "clpid": "Miller-A-A" }, { "family_name": "Hicks", "given_name": "Erin K. S.", "clpid": "Hicks-E-K-S" }, { "family_name": "Malkan", "given_name": "Matthew", "orcid": "0000-0001-6919-1237", "clpid": "Malkan-M-A" }, { "family_name": "Andreoni", "given_name": "Igor", "orcid": "0000-0002-8977-1498", "clpid": "Andreoni-I" }, { "family_name": "Bellm", "given_name": "Eric C.", "orcid": "0000-0001-8018-5348", "clpid": "Bellm-E-C" }, { "family_name": "Buchheim", "given_name": "Robert", "clpid": "Buchheim-R" }, { "family_name": "Dekany", "given_name": "Richard", "clpid": "Dekany-Richard" }, { "family_name": "Feeney", "given_name": "Michael", "clpid": "Feeney-M" }, { "family_name": "Frederick", "given_name": "Sara", "orcid": "0000-0001-9676-730X", "clpid": "Frederick-S" }, { "family_name": "Gal-Yam", "given_name": "A.", "orcid": "0000-0002-3653-5598", "clpid": "Gal-Yam-A" }, { "family_name": "Gehrz", "given_name": "R. D.", "orcid": "0000-0003-1319-4089", "clpid": "Gehrz-R-D" }, { "family_name": "Giomi", "given_name": "Matteo", "clpid": "Giomi-M" }, { "family_name": "Graham", "given_name": "Matthew J.", "orcid": "0000-0002-3168-0139", "clpid": "Graham-M-J" }, { "family_name": "Green", "given_name": "Wayne", "clpid": "Green-W" }, { "family_name": "Hale", "given_name": "David", "clpid": "Hale-D" }, { "family_name": "Hankins", "given_name": "Matthew J.", "orcid": "0000-0001-9315-8437", "clpid": "Hankins-M-J" }, { "family_name": "Hanson", "given_name": "Mark", "clpid": "Hanson-M" }, { "family_name": "Helou", "given_name": "George", "orcid": "0000-0003-3367-3415", "clpid": "Helou-G" }, { "family_name": "Ho", "given_name": "Anna Y. Q.", "orcid": "0000-0002-9017-3567", "clpid": "Ho-Anna-Y-Q" }, { "family_name": "Hung", "given_name": "T.", "clpid": "Hung-T" }, { "family_name": "Juri\u0107", "given_name": "Mario", "orcid": "0000-0003-1996-9252", "clpid": "Juri\u0107-M" }, { "family_name": "Kendurkar", "given_name": "Malhar R.", "clpid": "Kendurkar-M-R" }, { "family_name": "Kulkarni", "given_name": "S. R.", "orcid": "0000-0001-5390-8563", "clpid": "Kulkarni-S-R" }, { "family_name": "Lau", "given_name": "Ryan M.", "clpid": "Lau-Ryan-M" }, { "family_name": "Masci", "given_name": "Frank J.", "orcid": "0000-0002-8532-9395", "clpid": "Masci-F-J" }, { "family_name": "Neill", "given_name": "James D.", "orcid": "0000-0002-0466-1119", "clpid": "Neill-J-D" }, { "family_name": "Quin", "given_name": "Kevin", "clpid": "Quin-K" }, { "family_name": "Riddle", "given_name": "Reed", "orcid": "0000-0002-0387-370X", "clpid": "Riddle-R-L" }, { "family_name": "Rusholme", "given_name": "B.", "orcid": "0000-0001-7648-4142", "clpid": "Rusholme-B" }, { "family_name": "Sims", "given_name": "Forrest", "clpid": "Sims-F" }, { "family_name": "Smith", "given_name": "Nathan", "clpid": "Smith-N" }, { "family_name": "Smith", "given_name": "Roger M.", "clpid": "Smith-R-M" }, { "family_name": "Soumagnac", "given_name": "Maayane T.", "orcid": "0000-0001-6753-1488", "clpid": "Soumagnac-M-T" }, { "family_name": "Tachibana", "given_name": "Yutaro", "orcid": "0000-0001-6584-6945", "clpid": "Tachibana-Yutaro" }, { "family_name": "Tinyanont", "given_name": "Samaporn", "orcid": "0000-0002-1481-4676", "clpid": "Tinyanont-S" }, { "family_name": "Walters", "given_name": "Richard", "orcid": "0000-0002-1835-6078", "clpid": "Walters-R" }, { "family_name": "Watson", "given_name": "Stanley", "clpid": "Watson-S" }, { "family_name": "Williams", "given_name": "Robert E.", "clpid": "Williams-R-E" } ], "abstract": "We present the discovery of an optical transient (OT) in Messier 51, designated M51 OT2019-1 (also ZTF 19aadyppr, AT 2019abn, ATLAS19bzl), by the Zwicky Transient Facility (ZTF). The OT rose over 15 days to an observed luminosity of M_r = \u221213 (\u03bdL \u03bd = 9 \u00d7 10^6 L_\u2299), in the luminosity gap between novae and typical supernovae (SNe). Spectra during the outburst show a red continuum, Balmer emission with a velocity width of \u2248400 km s^(\u22121), Ca II and [Ca II] emission, and absorption features characteristic of an F-type supergiant. The spectra and multiband light curves are similar to the so-called \"SN impostors\" and intermediate-luminosity red transients (ILRTs). We directly identify the likely progenitor in archival Spitzer Space Telescope imaging with a 4.5 \u03bcm luminosity of M_([4.5]) \u2248 \u221212.2 mag and a [3.6]\u2013[4.5] color redder than 0.74 mag, similar to those of the prototype ILRTs SN 2008S and NGC 300 OT2008-1. Intensive monitoring of M51 with Spitzer further reveals evidence for variability of the progenitor candidate at [4.5] in the years before the OT. The progenitor is not detected in pre-outburst Hubble Space Telescope optical and near-IR images. The optical colors during outburst combined with spectroscopic temperature constraints imply a higher reddening of E(B \u2212 V) \u2248 0.7 mag and higher intrinsic luminosity of M_r \u2248 \u221214.9 mag (\u03bdL_\u03bd = 5.3 \u00d7 10^7 L\u2299) near peak than seen in previous ILRT candidates. Moreover, the extinction estimate is higher on the rise than on the plateau, suggestive of an extended phase of circumstellar dust destruction. These results, enabled by the early discovery of M51 OT2019-1 and extensive pre-outburst archival coverage, offer new clues about the debated origins of ILRTs and may challenge the hypothesis that they arise from the electron-capture induced collapse of extreme asymptotic giant branch stars.", "doi": "10.3847/2041-8213/ab2c05", "issn": "2041-8213", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal Letters", "publication_date": "2019-08-01", "series_number": "2", "volume": "880", "issue": "2", "pages": "Art. No. L20" }, { "id": "authors:00y0p-6tm72", "collection": "authors", "collection_id": "00y0p-6tm72", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190614-091205859", "type": "article", "title": "Uncovering Red and Dusty Ultraluminous X-Ray Sources with Spitzer", "author": [ { "family_name": "Lau", "given_name": "Ryan M.", "clpid": "Lau-Ryan-M" }, { "family_name": "Heida", "given_name": "Marianne", "orcid": "0000-0002-1082-7496", "clpid": "Heida-M" }, { "family_name": "Walton", "given_name": "Dominic J.", "orcid": "0000-0001-5819-3552", "clpid": "Walton-D-J" }, { "family_name": "Kasliwal", "given_name": "Mansi M.", "orcid": "0000-0002-5619-4938", "clpid": "Kasliwal-M-M" }, { "family_name": "Adams", "given_name": "Scott M.", "orcid": "0000-0001-5855-5939", "clpid": "Adams-Scott-M" }, { "family_name": "Cody", "given_name": "Ann Marie", "orcid": "0000-0002-3656-6706", "clpid": "Cody-A-M" }, { "family_name": "De", "given_name": "Kishalay", "orcid": "0000-0002-8989-0542", "clpid": "De-Kishalay" }, { "family_name": "Gehrz", "given_name": "Robert D.", "orcid": "0000-0003-1319-4089", "clpid": "Gehrz-R-D" }, { "family_name": "F\u00fcrst", "given_name": "Felix", "orcid": "0000-0003-0388-0560", "clpid": "F\u00fcrst-F" }, { "family_name": "Jencson", "given_name": "Jacob E.", "orcid": "0000-0001-5754-4007", "clpid": "Jencson-J-E" }, { "family_name": "Kennea", "given_name": "Jamie A.", "orcid": "0000-0002-6745-4790", "clpid": "Kennea-J-A" }, { "family_name": "Masci", "given_name": "Frank", "orcid": "0000-0002-8532-9395", "clpid": "Masci-F-J" } ], "abstract": "We present a mid-infrared (IR) sample study of nearby ultraluminous X-ray sources (ULXs) using multiepoch observations with the Infrared Array Camera (IRAC) on the Spitzer Space Telescope. Spitzer/IRAC observations taken after 2014 were obtained as part of the Spitzer Infrared Intensive Transients Survey. Our sample includes 96 ULXs located within 10 Mpc. Of the 96 ULXs, 12 have candidate counterparts consistent with absolute mid-IR magnitudes of supergiants, and 16 counterparts exceeded the mid-IR brightness of single supergiants and are thus more consistent with star clusters or non-ULX background active galactic nuclei. The supergiant candidate counterparts exhibit a bimodal color distribution in a Spitzer/IRAC color\u2013magnitude diagram, where \"red\" and \"'blue\" ULXs fall in IRAC colors [3.6] \u2013 [4.5] ~ 0.7 and [3.6] \u2013 [4.5] ~ 0.0, respectively. The mid-IR colors and absolute magnitudes of four \"red\" and five \"blue\" ULXs are consistent with those of supergiant B[e] (sgB[e]) and red supergiant (RSG) stars, respectively. Although \"blue,\" RSG-like mid-IR ULX counterparts likely host RSG mass donors; we propose that \"red\" counterparts are ULXs exhibiting the \"B[e] phenomenon\" rather than hosts of sgB[e] mass donors. We show that the mid-IR excess from the \"red\" ULXs is likely due to thermal emission from circumstellar or circumbinary dust. Using dust as a probe for total mass, we estimate mass-loss rates of \u1e40 ~ 1 x 10^(-4) M_\u2299 yr^(\u22121) in dust-forming outflows of red ULXs. Based on the transient mid-IR behavior and its relatively flat spectral index, \u03b1 = \u22120.19 \u00b1 0.1, we suggest that the mid-IR emission from Holmberg IX X-1 originates from a variable jet.", "doi": "10.3847/1538-4357/ab1b1c", "issn": "1538-4357", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal", "publication_date": "2019-06-10", "series_number": "1", "volume": "878", "issue": "1", "pages": "Art. No. 71" }, { "id": "authors:x8xwy-yx408", "collection": "authors", "collection_id": "x8xwy-yx408", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190531-091631048", "type": "article", "title": "SPIRITS Catalog of Infrared Variables: Identification of Extremely Luminous Long Period Variables", "author": [ { "family_name": "Karambelkar", "given_name": "V. R.", "clpid": "Karambelkar-V-R" }, { "family_name": "Adams", "given_name": "S. M.", "orcid": "0000-0001-5855-5939", "clpid": "Adams-Scott-M" }, { "family_name": "Whitelock", "given_name": "P. A.", "orcid": "0000-0002-4678-4432", "clpid": "Whitelock-P-A" }, { "family_name": "Kasliwal", "given_name": "M. M.", "orcid": "0000-0002-5619-4938", "clpid": "Kasliwal-M-M" }, { "family_name": "Jencson", "given_name": "J. E.", "orcid": "0000-0001-5754-4007", "clpid": "Jencson-J-E" }, { "family_name": "Boyer", "given_name": "M. L.", "orcid": "0000-0003-4850-9589", "clpid": "Boyer-M-L" }, { "family_name": "Goldman", "given_name": "S. R.", "orcid": "0000-0002-8937-3844", "clpid": "Goldman-S-R" }, { "family_name": "Masci", "given_name": "F.", "orcid": "0000-0002-8532-9395", "clpid": "Masci-F-J" }, { "family_name": "Cody", "given_name": "A. M.", "orcid": "0000-0002-3656-6706", "clpid": "Cody-A-M" }, { "family_name": "Bally", "given_name": "J.", "orcid": "0000-0001-8135-6612", "clpid": "Bally-J" }, { "family_name": "Bond", "given_name": "H. E.", "orcid": "0000-0003-1377-7145", "clpid": "Bond-H-E" }, { "family_name": "Gehrz", "given_name": "R. D.", "orcid": "0000-0003-1319-4089", "clpid": "Gehrz-R-D" }, { "family_name": "Parthasarathy", "given_name": "M.", "clpid": "Parthasarathy-M" }, { "family_name": "Lau", "given_name": "R. M.", "clpid": "Lau-Ryan-M" }, { "literal": "SPIRITS Collaboration" } ], "abstract": "We present a catalog of 417 luminous infrared variable stars with periods exceeding 250 days. These were identified in 20 nearby galaxies by the ongoing SPitzer InfraRed Intensive Transients Survey survey with the Spitzer Space Telescope. Of these, 359 variables have M_[4.5] (phase-weighted mean magnitudes) fainter than \u221212 and periods and luminosities consistent with previously reported variables in the Large Magellanic Cloud (LMC). However, 58 variables are more luminous than M_[4.5] = \u221212, including 11 that are brighter than M_[4.5] = \u221213, with the brightest having M_[4.5] = \u221215.51. Most of these bright variable sources have quasi-periods longer than 1000 days, including four over 2000 days. We suggest that the fundamental period\u2013luminosity relationship, previously measured for the LMC, extends to much higher luminosities and longer periods in this large galaxy sample. We posit that these variables include massive asymptotic giant branch (AGB) stars (possibly super-AGB stars), red supergiants experiencing exceptionally high mass-loss rates, and interacting binaries. We also present 3.6, 4.5, 5.8, and 8.0 \u03bcm photometric catalogs for all sources in these 20 galaxies.", "doi": "10.3847/1538-4357/ab1a41", "issn": "1538-4357", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal", "publication_date": "2019-06-01", "series_number": "2", "volume": "877", "issue": "2", "pages": "Art. No. 110" }, { "id": "authors:cmnnh-p0k21", "collection": "authors", "collection_id": "cmnnh-p0k21", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190520-125615362", "type": "article", "title": "SOFIA/FORCAST Observations of the Sgr A-H H ii Regions: Using Dust Emission to Elucidate the Heating Sources", "author": [ { "family_name": "Hankins", "given_name": "M. J.", "orcid": "0000-0001-9315-8437", "clpid": "Hankins-M-J" }, { "family_name": "Lau", "given_name": "R. M.", "clpid": "Lau-Ryan-M" }, { "family_name": "Mills", "given_name": "E. A. C.", "orcid": "0000-0001-8782-1992", "clpid": "Mills-E-A-C" }, { "family_name": "Morris", "given_name": "M. R.", "orcid": "0000-0002-6753-2066", "clpid": "Morris-M-R" }, { "family_name": "Herter", "given_name": "T. L.", "orcid": "0000-0002-3856-8385", "clpid": "Herter-T-L" } ], "abstract": "The Sgr A-H H II regions are a collection of sources that may represent one of the most recent sites of star formation in the Galactic center (GC). Examining these H II regions provides important information on the prevalence and distribution of massive stars in the region and may provide clues on the origin of other massive field stars throughout the GC. In this work, we present infrared imaging observations of the Sgr A-H H II regions taken with the Faint Object Infrared Camera for the SOFIA Telescope (FORCAST) at 19.7, 25.2, 31.5, and 37.1 \u03bcm. These data provide high angular resolution maps (~4'') of the sources, which allow us to study the morphology of spatially extended H II regions in detail. The wavelength coverage of FORCAST also supplies important constraints on the dust mass, temperature, and luminosity of the sources. We produce spectral energy distribution models using DustEM to measure the luminosity and dust mass, which range from ~3 \u00d7 10^3 to 6 \u00d7 10^5 L \u2299 and from ~6 \u00d7 10^(\u22124) to 3 \u00d7 10^(\u22121) M\u2299, respectively. Analysis of dust temperatures in the four spatially extended H II regions (H1, H2, H3, and H5) shows that three of these objects require multiple heating sources, and we identify potential stellar candidates. We also compare the size and morphology of the H II regions and demonstrate that the properties of H_2 are consistent with in situ star formation. Lastly, we identify nine additional sources that may be part of the H complex and provide initial characterizations of their infrared emission.", "doi": "10.3847/1538-4357/ab174e", "issn": "1538-4357", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal", "publication_date": "2019-05-20", "series_number": "1", "volume": "877", "issue": "1", "pages": "Art. No. 22" }, { "id": "authors:1yfh3-zj930", "collection": "authors", "collection_id": "1yfh3-zj930", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190313-132337168", "type": "article", "title": "Supernova 2017eaw: Molecule and Dust Formation from Infrared Observations", "author": [ { "family_name": "Tinyanont", "given_name": "Samaporn", "orcid": "0000-0002-1481-4676", "clpid": "Tinyanont-S" }, { "family_name": "Kasliwal", "given_name": "Mansi M.", "orcid": "0000-0002-5619-4938", "clpid": "Kasliwal-M-M" }, { "family_name": "Krafton", "given_name": "Kelsie", "clpid": "Krafton-K" }, { "family_name": "Lau", "given_name": "Ryan", "clpid": "Lau-Ryan-M" }, { "family_name": "Rho", "given_name": "Jeonghee", "orcid": "0000-0003-3643-839X", "clpid": "Rho-Jeonghee" }, { "family_name": "Leonard", "given_name": "Douglas C.", "clpid": "Leonard-D-C" }, { "family_name": "De", "given_name": "Kishalay", "orcid": "0000-0002-8989-0542", "clpid": "De-Kishalay" }, { "family_name": "Jencson", "given_name": "Jacob", "orcid": "0000-0001-5754-4007", "clpid": "Jencson-J-E" }, { "family_name": "Mawet", "given_name": "Dimitri", "orcid": "0000-0002-8895-4735", "clpid": "Mawet-D" }, { "family_name": "Millar-Blanchaer", "given_name": "Maxwell", "orcid": "0000-0001-6205-9233", "clpid": "Millar-Blanchaer-M-A" }, { "family_name": "Nilsson", "given_name": "Ricky", "orcid": "0000-0002-5408-4954", "clpid": "Nilsson-R" }, { "family_name": "Yan", "given_name": "Lin", "orcid": "0000-0003-1710-9339", "clpid": "Yan-Lin" }, { "family_name": "Gehrz", "given_name": "Robert D.", "orcid": "0000-0003-1319-4089", "clpid": "Gehrz-R-D" }, { "family_name": "Helou", "given_name": "George", "orcid": "0000-0003-3367-3415", "clpid": "Helou-G" }, { "family_name": "Van Dyk", "given_name": "Schuyler D.", "orcid": "0000-0001-9038-9950", "clpid": "Van-Dyk-S-D" }, { "family_name": "Serabyn", "given_name": "Eugene", "clpid": "Serabyn-E" }, { "family_name": "Fox", "given_name": "Ori D.", "orcid": "0000-0003-2238-1572", "clpid": "Fox-O-D" }, { "family_name": "Clayton", "given_name": "Geoffrey", "orcid": "0000-0002-0141-7436", "clpid": "Clayton-G" } ], "abstract": "We present infrared (IR) photometry and spectroscopy of the Type II-P SN 2017eaw and its progenitor in the nearby galaxy NGC 6946. Progenitor observations in the Ks band in four epochs from 1 yr to 1 day before the explosion reveal no significant variability in the progenitor star greater than 6% that lasts longer than 200 days. SN 2017eaw is a typical SN II-P with near-IR and mid-IR photometric evolution similar to those of SNe 2002hh and 2004et, other normal SNe II-P in the same galaxy. Spectroscopic monitoring during the plateau phase reveals a possible high-velocity He I 1.083 \u03bcm absorption line, indicative of a shock interaction with the circumstellar medium. Spectra between 389 and 480 days postexplosion reveal a strong CO first overtone emission at 389 days, with a line profile matching that of SN 1987A from the same epoch, indicating ~10^(\u22123) M\u2299 of CO at 1800 K. From the 389 days epoch until the most recent observation at 566 days, the first overtone feature fades while the 4.5 \u03bcm excess, likely from the CO fundamental band, remains. This behavior indicates that the CO has not been destroyed, but that the gas has cooled enough that the levels responsible for first overtone emissions are no longer populated. Finally, the evolution of Spitzer 3.6 \u03bcm photometry shows evidence for dust formation in SN 2017eaw, with a dust mass of 10^(\u22126) or 10^(\u22124) M\u2299 assuming carbonaceous or silicate grains, respectively.", "doi": "10.3847/1538-4357/ab0897", "issn": "1538-4357", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal", "publication_date": "2019-03-10", "series_number": "2", "volume": "873", "issue": "2", "pages": "Art. No. 127" }, { "id": "authors:gzmrt-e8657", "collection": "authors", "collection_id": "gzmrt-e8657", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180305-144310779", "type": "article", "title": "SPIRITS 16tn in NGC 3556: A heavily obscured and low-luminosity supernova at 8.8 Mpc", "author": [ { "family_name": "Jencson", "given_name": "Jacob E.", "orcid": "0000-0001-5754-4007", "clpid": "Jencson-J-E" }, { "family_name": "Kasliwal", "given_name": "Mansi M.", "orcid": "0000-0002-5619-4938", "clpid": "Kasliwal-M-M" }, { "family_name": "Adams", "given_name": "Scott M.", "orcid": "0000-0001-5855-5939", "clpid": "Adams-Scott-M" }, { "family_name": "Bond", "given_name": "Howard E.", "orcid": "0000-0003-1377-7145", "clpid": "Bond-H-E" }, { "family_name": "Lau", "given_name": "Ryan M.", "clpid": "Lau-Ryan-M" }, { "family_name": "Johansson", "given_name": "Joel", "orcid": "0000-0001-5975-290X", "clpid": "Johansson-J" }, { "family_name": "Horesh", "given_name": "Assaf", "orcid": "0000-0002-5936-1156", "clpid": "Horesh-A" }, { "family_name": "Mooley", "given_name": "Kunal P.", "orcid": "0000-0002-2557-5180", "clpid": "Mooley-Kunal-Prakash" }, { "family_name": "Fender", "given_name": "Robert", "clpid": "Fender-Robert" }, { "family_name": "De", "given_name": "Kishalay", "orcid": "0000-0002-8989-0542", "clpid": "De-Kishalay" }, { "family_name": "O'Sullivan", "given_name": "D\u00f3nal", "orcid": "0000-0002-4959-9179", "clpid": "O'Sullivan-Donal" }, { "family_name": "Masci", "given_name": "Frank J.", "orcid": "0000-0002-8532-9395", "clpid": "Masci-F-J" }, { "family_name": "Cody", "given_name": "Ann Marie", "orcid": "0000-0002-3656-6706", "clpid": "Cody-A-M" }, { "family_name": "Blagorodnova", "given_name": "Nadia", "orcid": "0000-0003-0901-1606", "clpid": "Blagorodnova-N" }, { "family_name": "Fox", "given_name": "Ori D.", "orcid": "0000-0003-2238-1572", "clpid": "Fox-O-D" }, { "family_name": "Gehrz", "given_name": "Robert D.", "orcid": "0000-0003-1319-4089", "clpid": "Gehrz-R-D" }, { "family_name": "Milne", "given_name": "Peter A.", "orcid": "0000-0002-0370-157X", "clpid": "Milne-P-A" }, { "family_name": "Perley", "given_name": "Daniel A.", "orcid": "0000-0001-8472-1996", "clpid": "Perley-D-A" }, { "family_name": "Smith", "given_name": "Nathan", "clpid": "Smith-Nathan" }, { "family_name": "Van Dyk", "given_name": "Schuyler D.", "orcid": "0000-0001-9038-9950", "clpid": "Van-Dyk-S-D" } ], "abstract": "We present the discovery by the SPitzer InfraRed Intensive Transients Survey (SPIRITS) of a likely supernova (SN) in NGC 3556 (M108) at only 8.8 Mpc that was not detected by optical searches. A luminous infrared (IR) transient at M_([4.5]) = \u221216.7 mag (Vega), SPIRITS 16tn is coincident with a dust lane in the inclined, star-forming disk of the host. Using observations in the IR, optical, and radio, we attempt to determine the nature of this event. We estimate A_V \u2248 8\u20139 mag of extinction, placing it among the three most highly obscured IR-discovered SNe. The [4.5] light curve declined at a rate of 0.013 mag day^(\u22121), and the [3.6]\u2013[4.5] color increased from 0.7 to \u2273 1.0 mag by 184.7 days post discovery. Optical/IR spectroscopy shows a red continuum but no clearly discernible features, preventing a definitive spectroscopic classification. Radio observations constrain the radio luminosity of SPIRITS 16tn to L_\u03bd \u227e 10^(24) erg s^(\u22121) Hz^(\u22121) between 3 and 15 GHz, excluding many varieties of core-collapse SNe. An SN Ia is ruled out by the observed IR color and lack of spectroscopic features from Fe-peak elements. SPIRITS 16tn was fainter at [4.5] than typical stripped-envelope SNe by \u22481 mag. Comparison of the spectral energy distribution to SNe II suggests that SPIRITS 16tn was both highly obscured and intrinsically dim, possibly akin to the low-luminosity SN 2005cs. We infer the presence of an IR dust echo powered by an initial peak luminosity of the transient of 5 \u00d7 10^(40) erg s^(\u22121) \u227e L_(peak) \u227e 4 \u00d7 10^(43) erg s^(\u22121), consistent with the observed range for SNe II. This discovery illustrates the power of IR surveys to overcome the compounding effects of visible extinction and optically subluminous events in completing the inventory of nearby SNe.", "doi": "10.3847/1538-4357/aacf8b", "issn": "1538-4357", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal", "publication_date": "2018-08-10", "series_number": "1", "volume": "863", "issue": "1", "pages": "Art. No. 20" }, { "id": "authors:680qt-xjs07", "collection": "authors", "collection_id": "680qt-xjs07", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180808-160605291", "type": "article", "title": "Dust Production Rates in the Fomalhaut Debris Disk from SOFIA/FORCAST Mid-infrared Imaging", "author": [ { "family_name": "Adams", "given_name": "J. D.", "orcid": "0000-0001-7645-8913", "clpid": "Adams-J-D" }, { "family_name": "Herter", "given_name": "T. L.", "orcid": "0000-0002-3856-8385", "clpid": "Herter-T-L" }, { "family_name": "Lau", "given_name": "R. M.", "clpid": "Lau-Ryan-M" }, { "family_name": "Trinh", "given_name": "C.", "clpid": "Trinh-Cong" }, { "family_name": "Hankins", "given_name": "M.", "orcid": "0000-0001-9315-8437", "clpid": "Hankins-M-J" } ], "abstract": "We present the first spatially resolved mid-infrared (37.1 \u03bcm) image of the Fomalhaut debris disk. We use point spread function fitting and subtraction to distinctly measure the flux from the unresolved component and the debris disk. We measure an infrared excess in the point source of 0.9 \u00b1 0.2 Jy, consistent with emission from warm dust in an inner disk structure, and inconsistent with a stellar wind origin. We cannot confirm or rule out the presence of a pileup ring near the star. In the cold region, the 37 \u03bcm imaging is sensitive to emission from small, blowout grains, which is an excellent probe of the dust production rate from planetesimal collisions. Under the assumptions that the dust grains are icy aggregates and the debris disk is in steady state, this result is consistent with the dust production rates predicted by Kenyon & Bromley from theoretical models of icy planet formation. We find a dust luminosity of (7.9 \u00b1 0.8) \u00d7 10^(\u22124) L\u2299 and a dust mass of 8\u201316 lunar masses, depending on grain porosity, with ~1 lunar mass in grains with radius 1 \u03bcm\u20131 mm. If the grains are icy and highly porous, meter-sized objects must be invoked to explain the far-infrared, submm, and mm emission. If the grains are composed of astronomical silicates, there is a dearth of blowout grains and the mass loss rate is well below the predicted dust production values.", "doi": "10.3847/1538-4357/aacf96", "issn": "1538-4357", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal", "publication_date": "2018-08-01", "series_number": "2", "volume": "862", "issue": "2", "pages": "Art. No. 161" }, { "id": "authors:av3yr-mdj98", "collection": "authors", "collection_id": "av3yr-mdj98", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180325-185226577", "type": "article", "title": "A Potential Cyclotron Resonant Scattering Feature in the Ultraluminous X-Ray Source Pulsar NGC 300 ULX1 Seen by NuSTAR and XMM-Newton", "author": [ { "family_name": "Walton", "given_name": "D. J.", "orcid": "0000-0001-5819-3552", "clpid": "Walton-D-J" }, { "family_name": "Bachetti", "given_name": "M.", "orcid": "0000-0002-4576-9337", "clpid": "Bachetti-M" }, { "family_name": "F\u00fcrst", "given_name": "F.", "orcid": "0000-0003-0388-0560", "clpid": "F\u00fcrst-F" }, { "family_name": "Barret", "given_name": "D.", "orcid": "0000-0002-0393-9190", "clpid": "Barret-D" }, { "family_name": "Brightman", "given_name": "M.", "orcid": "0000-0002-8147-2602", "clpid": "Brightman-M" }, { "family_name": "Fabian", "given_name": "A. C.", "orcid": "0000-0002-9378-4072", "clpid": "Fabian-A-C" }, { "family_name": "Grefenstette", "given_name": "B. W.", "orcid": "0000-0002-1984-2932", "clpid": "Grefenstette-B-W" }, { "family_name": "Harrison", "given_name": "F. A.", "orcid": "0000-0002-4226-8959", "clpid": "Harrison-F-A" }, { "family_name": "Heida", "given_name": "M.", "orcid": "0000-0002-1082-7496", "clpid": "Heida-M" }, { "family_name": "Kennea", "given_name": "J.", "orcid": "0000-0002-6745-4790", "clpid": "Kennea-J-A" }, { "family_name": "Kosec", "given_name": "P.", "clpid": "Kosec-P" }, { "family_name": "Lau", "given_name": "R. M.", "clpid": "Lau-Ryan-M" }, { "family_name": "Madsen", "given_name": "K. K.", "orcid": "0000-0003-1252-4891", "clpid": "Madsen-K-K" }, { "family_name": "Middleton", "given_name": "M. J.", "orcid": "0000-0002-8183-2970", "clpid": "Middleton-M-J" }, { "family_name": "Pinto", "given_name": "C.", "orcid": "0000-0003-2532-7379", "clpid": "Pinto-C" }, { "family_name": "Steiner", "given_name": "J. F.", "orcid": "0000-0002-5872-6061", "clpid": "Steiner-J-F" }, { "family_name": "Webb", "given_name": "N.", "clpid": "Webb-N-A" } ], "abstract": "Based on phase-resolved broadband spectroscopy using XMM-Newton and NuSTAR, we report on a potential cyclotron resonant scattering feature (CRSF) at E ~ 13 keV in the pulsed spectrum of the recently discovered ultraluminous X-ray source (ULX) pulsar NGC 300 ULX1. If this interpretation is correct, the implied magnetic field of the central neutron star is B ~ 1012 G (assuming scattering by electrons), similar to that estimated from the observed spin-up of the star, and also similar to known Galactic X-ray pulsars. We discuss the implications of this result for the connection between NGC 300 ULX1 and the other known ULX pulsars, particularly in light of the recent discovery of a likely proton cyclotron line in another ULX, M51 ULX-8.", "doi": "10.3847/2041-8213/aabadc", "issn": "2041-8213", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal Letters", "publication_date": "2018-04-10", "series_number": "1", "volume": "857", "issue": "1", "pages": "Art. No. L3" }, { "id": "authors:8tq2d-wpw08", "collection": "authors", "collection_id": "8tq2d-wpw08", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180328-133306261", "type": "article", "title": "An Optical and Infrared Time-domain Study of the Supergiant Fast X-Ray Transient Candidate IC 10 X-2", "author": [ { "family_name": "Kwan", "given_name": "Stephanie", "orcid": "0000-0002-5308-7707", "clpid": "Kwan-Stephanie" }, { "family_name": "Lau", "given_name": "Ryan M.", "clpid": "Lau-Ryan-M" }, { "family_name": "Jencson", "given_name": "Jacob", "orcid": "0000-0001-5754-4007", "clpid": "Jencson-J-E" }, { "family_name": "Kasliwal", "given_name": "Mansi M.", "orcid": "0000-0002-5619-4938", "clpid": "Kasliwal-M-M" }, { "family_name": "Boyer", "given_name": "Martha L.", "orcid": "0000-0003-4850-9589", "clpid": "Boyer-M-L" }, { "family_name": "Ofek", "given_name": "Eran", "orcid": "0000-0002-6786-8774", "clpid": "Ofek-E-O" }, { "family_name": "Masci", "given_name": "Frank", "orcid": "0000-0002-8532-9395", "clpid": "Masci-F-J" }, { "family_name": "Laher", "given_name": "Russ", "orcid": "0000-0003-2451-5482", "clpid": "Laher-R-R" } ], "abstract": "We present an optical and infrared (IR) study of IC 10 X-2, a high-mass X-ray binary in the galaxy IC 10. Previous optical and X-ray studies suggest that X-2 is a Supergiant Fast X-ray Transient: a large-amplitude (factor of ~100), short-duration (hours to weeks) X-ray outburst on 2010 May 21. We analyze R- and g-band light curves of X-2 from the intermediate Palomar Transient Factory taken between 2013 July 15 and 2017 February 14 that show high-amplitude (\u2273 1 mag), short-duration (\u227e 8 days) flares and dips (\u2273 0.5 mag). Near-IR spectroscopy of X-2 from Palomar/TripleSpec show He i, Paschen-\u03b3, and Paschen-\u03b2 emission lines with similar shapes and amplitudes as those of luminous blue variables (LBVs) and LBV candidates (LBVc). Mid-IR colors and magnitudes from Spitzer/Infrared Array Camera photometry of X-2 resemble those of known LBV/LBVcs. We suggest that the stellar companion in X-2 is an LBV/LBVc and discuss possible origins of the optical flares. Dips in the optical light curve are indicative of eclipses from optically thick clumps formed in the winds of the stellar counterpart. Given the constraints on the flare duration (0.02\u20130.8 days) and the time between flares (15.1 \u00b1 7.8 days), we estimate the clump volume filling factor in the stellar winds, f_V , to be $.01 < {f_V < 0.71, which overlaps with values measured from massive star winds. In X-2, we interpret the origin of the optical flares as the accretion of clumps formed in the winds of an LBV/LBVc onto the compact object.", "doi": "10.3847/1538-4357/aaaf73", "issn": "1538-4357", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal", "publication_date": "2018-03-20", "series_number": "1", "volume": "856", "issue": "1", "pages": "Art. No. 38" }, { "id": "authors:zeqjz-dd973", "collection": "authors", "collection_id": "zeqjz-dd973", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170929-091827113", "type": "article", "title": "Illuminating Gravitational Waves: A Concordant Picture of Photons from a Neutron Star Merger", "author": [ { "family_name": "Kasliwal", "given_name": "M. M.", "orcid": "0000-0002-5619-4938", "clpid": "Kasliwal-M-M" }, { "family_name": "Cook", "given_name": "D. O.", "orcid": "0000-0002-6877-7655", "clpid": "Cook-D-O" }, { "family_name": "Lau", "given_name": "R. M.", "clpid": "Lau-Ryan-M" }, { "family_name": "Fremling", "given_name": "C.", "orcid": "0000-0002-4223-103X", "clpid": "Fremling-C" }, { "family_name": "Jencson", "given_name": "J. E.", "orcid": "0000-0001-5754-4007", "clpid": "Jencson-J-E" }, { "family_name": "Adams", "given_name": "S. M.", "orcid": "0000-0001-5855-5939", "clpid": "Adams-Scott-M" }, { "family_name": "Blagorodnova", "given_name": "N.", "orcid": "0000-0003-0901-1606", "clpid": "Blagorodnova-N" }, { "family_name": "Cannella", "given_name": "C.", "orcid": "0000-0003-2667-7290", "clpid": "Cannella-C-B" }, { "family_name": "De", "given_name": "K.", "orcid": "0000-0002-8989-0542", "clpid": "De-Kishalay" }, { "family_name": "Hallinan", "given_name": "G.", "orcid": "0000-0002-7083-4049", "clpid": "Hallinan-G" }, { "family_name": "Harrison", "given_name": "F.", "orcid": "0000-0002-4226-8959", "clpid": "Harrison-F-A" }, { "family_name": "Ho", "given_name": "A. Y. Q.", "orcid": "0000-0002-9017-3567", "clpid": "Ho-Anna-Y-Q" }, { "family_name": "Kupfer", "given_name": "T.", "orcid": "0000-0002-6540-1484", "clpid": "Kupfer-T" }, { "family_name": "Madsen", "given_name": "K.", "orcid": "0000-0003-1252-4891", "clpid": "Madsen-K-K" }, { "family_name": "Xu", "given_name": "Y.", "clpid": "Xu-Yong" }, { "family_name": "Yan", "given_name": "L.", "orcid": "0000-0003-1710-9339", "clpid": "Yan-Lin" }, { "family_name": "Helou", "given_name": "G.", "orcid": "0000-0003-3367-3415", "clpid": "Helou-G" } ], "abstract": "Merging neutron stars offer an exquisite laboratory for simultaneously studying strong-field gravity and matter in extreme environments. We establish the physical association of an electromagnetic counterpart (EM170817) to gravitational waves (GW170817) detected from merging neutron stars. By synthesizing a panchromatic dataset, we demonstrate that merging neutron stars are a long-sought production site forging heavy elements by r-process nucleosynthesis. The weak gamma-rays seen in EM170817 are dissimilar to classical short gamma-ray bursts with ultra-relativistic jets. Instead, we suggest that breakout of a wide-angle, mildly-relativistic cocoon engulfing the jet elegantly explains the low-luminosity gamma-rays, the high-luminosity ultraviolet-optical-infrared and the delayed radio/x-ray emission. We posit that all merging neutron stars may lead to a wide-angle cocoon breakout; sometimes accompanied by a successful jet and sometimes a choked jet.", "doi": "10.1126/science.aap9455", "issn": "0036-8075", "publisher": "American Association for the Advancement of Science", "publication": "Science", "publication_date": "2017-12-22", "series_number": "6370", "volume": "358", "issue": "6370", "pages": "1559-1565" }, { "id": "authors:ccn78-xj102", "collection": "authors", "collection_id": "ccn78-xj102", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180105-132009429", "type": "article", "title": "Follow Up of GW170817 and Its Electromagnetic Counterpart by Australian-Led Observing Programmes", "author": [ { "family_name": "Andreoni", "given_name": "I.", "orcid": "0000-0002-8977-1498", "clpid": "Andreoni-I" }, { "family_name": "Kasliwal", "given_name": "M.", "orcid": "0000-0002-5619-4938", "clpid": "Kasliwal-M-M" }, { "family_name": "Lau", "given_name": "R.", "clpid": "Lau-Ryan-M" } ], "abstract": "The discovery of the first electromagnetic counterpart to a gravitational wave signal has generated follow-up observations by over 50 facilities world-wide, ushering in the new era of multi-messenger astronomy. In this paper, we present follow-up observations of the gravitational wave event GW170817 and its electromagnetic counterpart SSS17a/DLT17ck (IAU label AT2017gfo) by 14 Australian telescopes and partner observatories as part of Australian-based and Australian-led research programs. We report early- to late-time multi-wavelength observations, including optical imaging and spectroscopy, mid-infrared imaging, radio imaging, and searches for fast radio bursts. Our optical spectra reveal that the transient source emission cooled from approximately 6 400 K to 2 100 K over a 7-d period and produced no significant optical emission lines. The spectral profiles, cooling rate, and photometric light curves are consistent with the expected outburst and subsequent processes of a binary neutron star merger. Star formation in the host galaxy probably ceased at least a Gyr ago, although there is evidence for a galaxy merger. Binary pulsars with short (100 Myr) decay times are therefore unlikely progenitors, but pulsars like PSR B1534+12 with its 2.7 Gyr coalescence time could produce such a merger. The displacement (~2.2 kpc) of the binary star system from the centre of the main galaxy is not unusual for stars in the host galaxy or stars originating in the merging galaxy, and therefore any constraints on the kick velocity imparted to the progenitor are poor.", "doi": "10.1017/pasa.2017.65", "issn": "1323-3580", "publisher": "Cambridge University Press", "publication": "Publications of the Astronomical Society of Australia", "publication_date": "2017-12-20", "volume": "34", "pages": "Art. No. e069" }, { "id": "authors:jbtqq-f3r28", "collection": "authors", "collection_id": "jbtqq-f3r28", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170419-090643097", "type": "article", "title": "SPIRITS: Uncovering Unusual Infrared Transients with Spitzer", "author": [ { "family_name": "Kasliwal", "given_name": "Mansi M.", "orcid": "0000-0002-5619-4938", "clpid": "Kasliwal-M-M" }, { "family_name": "Masci", "given_name": "Frank", "orcid": "0000-0002-8532-9395", "clpid": "Masci-F-J" }, { "family_name": "Jencson", "given_name": "Jacob E.", "orcid": "0000-0001-5754-4007", "clpid": "Jencson-J-E" }, { "family_name": "Tinyanont", "given_name": "Samaporn", "orcid": "0000-0002-1481-4676", "clpid": "Tinyanont-S" }, { "family_name": "Cao", "given_name": "Yi", "orcid": "0000-0002-8036-8491", "clpid": "Cao-Yi" }, { "family_name": "Armus", "given_name": "Lee", "orcid": "0000-0003-3498-2973", "clpid": "Armus-L" }, { "family_name": "Cook", "given_name": "David O.", "orcid": "0000-0002-6877-7655", "clpid": "Cook-D-O" }, { "family_name": "Helou", "given_name": "George", "orcid": "0000-0003-3367-3415", "clpid": "Helou-G" }, { "family_name": "Lau", "given_name": "Ryan M.", "clpid": "Lau-Ryan-M" }, { "family_name": "Moore", "given_name": "Anna", "orcid": "0000-0002-2894-6936", "clpid": "Moore-A-M" }, { "family_name": "O'Sullivan", "given_name": "Donal", "orcid": "0000-0002-4959-9179", "clpid": "O'Sullivan-Donal" }, { "family_name": "Perez", "given_name": "Andres", "clpid": "Perez-Andres" }, { "family_name": "Prince", "given_name": "Thomas A.", "orcid": "0000-0002-8850-3627", "clpid": "Prince-T-A" }, { "family_name": "Van Dyk", "given_name": "Schuyler D.", "orcid": "0000-0001-9038-9950", "clpid": "Van-Dyk-S-D" } ], "abstract": "We present an ongoing, five-year systematic search for extragalactic infrared transients, dubbed SPIRITS\u2014SPitzer InfraRed Intensive Transients Survey. In the first year, using Spitzer/IRAC, we searched 190 nearby galaxies with cadence baselines of one month and six months. We discovered over 1958 variables and 43 transients. Here, we describe the survey design and highlight 14 unusual infrared transients with no optical counterparts to deep limits, which we refer to as SPRITEs (eSPecially Red Intermediate-luminosity Transient Events). SPRITEs are in the infrared luminosity gap between novae and supernovae, with [4.5] absolute magnitudes between \u221211 and \u221214 (Vega-mag) and [3.6]\u2013[4.5] colors between 0.3 mag and 1.6 mag. The photometric evolution of SPRITEs is diverse, ranging from <0.1 mag yr^(\u22121) to >7 mag yr^(\u22121). SPRITEs occur in star-forming galaxies. We present an in-depth study of one of them, SPIRITS 14ajc in Messier 83, which shows shock-excited molecular hydrogen emission. This shock may have been triggered by the dynamic decay of a non-hierarchical system of massive stars that led to either the formation of a binary or a protostellar merger.", "doi": "10.3847/1538-4357/aa6978", "issn": "1538-4357", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal", "publication_date": "2017-04-20", "series_number": "2", "volume": "839", "issue": "2", "pages": "Art. No. 88" }, { "id": "authors:yjfyh-tar59", "collection": "authors", "collection_id": "yjfyh-tar59", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170331-092410654", "type": "article", "title": "First Detection of Mid-infrared Variability from an Ultraluminous X-Ray Source Holmberg II X-1", "author": [ { "family_name": "Lau", "given_name": "R. M.", "clpid": "Lau-Ryan-M" }, { "family_name": "Heida", "given_name": "M.", "orcid": "0000-0002-1082-7496", "clpid": "Heida-M" }, { "family_name": "Kasliwal", "given_name": "M. M.", "orcid": "0000-0002-5619-4938", "clpid": "Kasliwal-M-M" }, { "family_name": "Walton", "given_name": "D. J.", "orcid": "0000-0001-5819-3552", "clpid": "Walton-D-J" } ], "abstract": "We present mid-infrared (IR) light curves of the Ultraluminous X-ray Source (ULX) Holmberg II X-1 from observations taken between 2014 January 13 and 2017 January 5 with the Spitzer Space Telescope at 3.6 and 4.5 \u03bcm in the Spitzer Infrared Intensive Transients Survey. The mid-IR light curves, which reveal the first detection of mid-IR variability from a ULX, is determined to arise primarily from dust emission rather than from a jet or an accretion disk outflow. We derived the evolution of the dust temperature (T_d ~ 600-800 K), IR luminosity (L_(IR) ~ 3 x 10^4 L_\u2299), mass (M_d ~ 1-3 x 10^(-6) M_\u2299), and equilibrium temperature radius (R_(eq) ~ 10-20 au). A comparison of X-1 with a sample of spectroscopically identified massive stars in the Large Magellanic Cloud on a mid-IR color\u2013magnitude diagram suggests that the mass donor in X-1 is a supergiant (sg) B[e]-star. The sgB[e]-interpretation is consistent with the derived dust properties and the presence of the [Fe ii] (\u03bb =1.644 \u00b5m) emission line revealed from previous near-IR studies of X-1. We attribute the mid-IR variability of X-1 to the increased heating of dust located in a circumbinary torus. It is unclear what physical processes are responsible for the increased dust heating; however, it does not appear to be associated with the X-ray flux from the ULX, given the constant X-ray luminosities provided by serendipitous, near-contemporaneous X-ray observations around the first mid-IR variability event in 2014. Our results highlight the importance of mid-IR observations of luminous X-ray sources traditionally studied at X-ray and radio wavelengths.", "doi": "10.3847/2041-8213/aa6746", "issn": "2041-8205", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal Letters", "publication_date": "2017-04-01", "series_number": "2", "volume": "838", "issue": "2", "pages": "Art. No. L17" }, { "id": "authors:f0qpx-nfw79", "collection": "authors", "collection_id": "f0qpx-nfw79", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160126-083711618", "type": "article", "title": "A Systematic Study of Mid-Infrared Emission from Core-Collapse Supernovae with SPIRITS", "author": [ { "family_name": "Tinyanont", "given_name": "Samaporn", "orcid": "0000-0002-1481-4676", "clpid": "Tinyanont-S" }, { "family_name": "Kasliwal", "given_name": "Mansi M.", "orcid": "0000-0002-5619-4938", "clpid": "Kasliwal-M-M" }, { "family_name": "Fox", "given_name": "Ori D.", "orcid": "0000-0003-2238-1572", "clpid": "Fox-O-D" }, { "family_name": "Lau", "given_name": "Ryan", "clpid": "Lau-Ryan-M" }, { "family_name": "Smith", "given_name": "Nathan", "clpid": "Smith-Nathan" }, { "family_name": "Williams", "given_name": "Robert", "clpid": "Williams-R" }, { "family_name": "Jencson", "given_name": "Jacob", "orcid": "0000-0001-5754-4007", "clpid": "Jencson-J-E" }, { "family_name": "Perley", "given_name": "Daniel", "orcid": "0000-0001-8472-1996", "clpid": "Perley-D-A" }, { "family_name": "Dykhoff", "given_name": "Devin", "clpid": "Dykhoff-D" }, { "family_name": "Gehrz", "given_name": "Robert", "orcid": "0000-0003-1319-4089", "clpid": "Gehrz-R-D" }, { "family_name": "Johansson", "given_name": "Joel", "orcid": "0000-0001-5975-290X", "clpid": "Johansson-J" }, { "family_name": "Van Dyk", "given_name": "Schuyler D.", "orcid": "0000-0001-9038-9950", "clpid": "Van-Dyk-S-D" }, { "family_name": "Masci", "given_name": "Frank", "orcid": "0000-0002-8532-9395", "clpid": "Masci-F-J" }, { "family_name": "Cody", "given_name": "Ann Marie", "orcid": "0000-0002-3656-6706", "clpid": "Cody-A-M" }, { "family_name": "Prince", "given_name": "Tom", "orcid": "0000-0002-8850-3627", "clpid": "Prince-T-A" } ], "abstract": "We present a systematic study of mid-infrared emission from 141 nearby supernovae (SNe) observed with Spitzer/IRAC as part of the ongoing SPIRITS survey. We detect 8 Type Ia and 36 core-collapse SNe. All Type Ia/Ibc SNe become undetectable within three years of explosion, whereas 22 \u00b1 11% of Type II SNe continue to be detected. Five Type II SNe are detected even two decades after discovery (SN 1974E, 1979C, 1980K, 1986J, and 1993J). Warm dust luminosity, temperature, and a lower limit on mass are obtained by fitting the two IRAC bands, assuming an optically thin dust shell. We derive warm dust masses between 10^(\u22126) and 10^(\u22122) M\u2299 and dust color temperatures between 200 and 1280 K. This observed warm dust could be pre-existing or newly created, but in either case represents a lower limit to the dust mass because cooler dust may be present. We present three case studies of extreme SNe. SN 2011ja (II-P) was over-luminous ([4.5] = \u221215.6 mag) at 900 days post explosion with increasing hot dust mass, suggesting either an episode of dust formation or intensifying circumstellar material (CSM) interactions heating up pre-existing dust. SN 2014bi (II-P) showed a factor of 10 decrease in dust mass over one month, suggesting either dust destruction or reduced dust heating. The IR luminosity of SN 2014C (Ib) stayed constant over 800 days, possibly due to strong CSM interaction with an H-rich shell, which is rare among stripped-envelope SNe. The observations suggest that this CSM shell originated from an LBV-like eruption roughly 100 years pre-explosion. The observed diversity demonstrates the power of mid-IR observations of a large sample of SNe.", "doi": "10.3847/1538-4357/833/2/231", "issn": "0004-637X", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal", "publication_date": "2016-12-20", "series_number": "2", "volume": "833", "issue": "2", "pages": "Art. No. 231" }, { "id": "authors:m4dek-77t09", "collection": "authors", "collection_id": "m4dek-77t09", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161018-122908941", "type": "article", "title": "Rising from the Ashes: Mid-infrared Re-brightening of the Impostor SN 2010da in NGC 300", "author": [ { "family_name": "Lau", "given_name": "Ryan M.", "clpid": "Lau-Ryan-M" }, { "family_name": "Kasliwal", "given_name": "Mansi M.", "orcid": "0000-0002-5619-4938", "clpid": "Kasliwal-M-M" }, { "family_name": "Bond", "given_name": "Howard E.", "orcid": "0000-0003-1377-7145", "clpid": "Bond-H-E" }, { "family_name": "Smith", "given_name": "Nathan", "clpid": "Smith-Nathan" }, { "family_name": "Fox", "given_name": "Ori D.", "orcid": "0000-0003-2238-1572", "clpid": "Fox-O-D" }, { "family_name": "Carlon", "given_name": "Robert", "clpid": "Carlon-R" }, { "family_name": "Cody", "given_name": "Ann Marie", "orcid": "0000-0002-3656-6706", "clpid": "Cody-A-M" }, { "family_name": "Contreras", "given_name": "Carlos", "clpid": "Contreras-C" }, { "family_name": "Dykhoff", "given_name": "Devin", "clpid": "Dykhoff-D" }, { "family_name": "Gehrz", "given_name": "Robert", "orcid": "0000-0003-1319-4089", "clpid": "Gehrz-R-D" }, { "family_name": "Hsiao", "given_name": "Eric", "clpid": "Hsiao-Eric-Y-Astro" }, { "family_name": "Jencson", "given_name": "Jacob", "orcid": "0000-0001-5754-4007", "clpid": "Jencson-J-E" }, { "family_name": "Khan", "given_name": "Rubab", "clpid": "Khan-Rubab" }, { "family_name": "Masci", "given_name": "Frank", "orcid": "0000-0002-8532-9395", "clpid": "Masci-F-J" }, { "family_name": "Monard", "given_name": "L. A. G.", "clpid": "Monard-L-A-G" }, { "family_name": "Monson", "given_name": "Andrew J.", "orcid": "0000-0002-0048-2586", "clpid": "Monson-A-J" }, { "family_name": "Morrell", "given_name": "Nidia", "orcid": "0000-0003-2535-3091", "clpid": "Morrell-N" }, { "family_name": "Phillips", "given_name": "Mark", "orcid": "0000-0003-2734-0796", "clpid": "Phillips-M-M" }, { "family_name": "Ressler", "given_name": "Michael E.", "clpid": "Ressler-M-E" } ], "abstract": "We present multi-epoch mid-infrared (IR) photometry and the optical discovery observations of the \"impostor\" supernova (SN) 2010da in NGC 300 using new and archival Spitzer Space Telescope images and ground-based observatories. The mid-infrared counterpart of SN 2010da was detected as Spitzer Infrared Intensive Transient Survey (SPIRITS) 14bme in the SPIRITS, an ongoing systematic search for IR transients. Before erupting on 2010 May 24, the SN 2010da progenitor exhibited a constant mid-IR flux at 3.6 and only a slight ~10% decrease at 4.5 \u03bcm between 2003 November and 2007 December. A sharp increase in the 3.6 \u03bcm flux followed by a rapid decrease measured ~150 days before and ~80 days after the initial outburst, respectively, reveal a mid-IR counterpart to the coincident optical and high luminosity X-ray outbursts. At late times, after the outburst (~2000 days), the 3.6 and 4.5 \u03bcm emission increased to over a factor of two times the progenitor flux and is currently observed (as of 2016 Feb) to be fading, but still above the progenitor flux. We attribute the re-brightening mid-IR emission to continued dust production and increasing luminosity of the surviving system associated with SN 2010da. We analyze the evolution of the dust temperature (T_d ~ 700\u20131000 K), mass (M_d ~ 0.5\u20133.8 \u00d7 10^(\u22127) M\u2299), luminosity (L_(IR) ~ 1.3\u20133.5 \u00d7 10^4 L\u2299), and the equilibrium temperature radius (R_(eq) ~ 6.4\u201312.2 au) in order to resolve the nature of SN 2010da. We address the leading interpretation of SN 2010da as an eruption from a luminous blue variable high-mass X-ray binary (HMXB) system. We propose that SN 2010da is instead a supergiant (sg)B[e]-HMXB based on similar luminosities and dust masses exhibited by two other known sgB[e]-HMXB systems. Additionally, the SN 2010da progenitor occupies a similar region on a mid-IR color\u2013magnitude diagram (CMD) with known sgB[e] stars in the Large Magellanic Cloud. The lower limit estimated for the orbital eccentricity of the sgB[e]-HMXB (e > 0.82) from X-ray luminosity measurements is high compared to known sgHMXBs and supports the claim that SN 2010da may be associated with a newly formed HMXB system.", "doi": "10.3847/0004-637X/830/2/142", "issn": "0004-637X", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal", "publication_date": "2016-10-20", "series_number": "2", "volume": "830", "issue": "2", "pages": "Art. No. 142" }, { "id": "authors:1j6ev-3sf55", "collection": "authors", "collection_id": "1j6ev-3sf55", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160105-112842026", "type": "article", "title": "SOFIA/FORCAST Observations of Warm Dust in S106: A Fragmented Environment", "author": [ { "family_name": "Adams", "given_name": "J. D.", "orcid": "0000-0001-7645-8913", "clpid": "Adams-J-D" }, { "family_name": "Herter", "given_name": "T. L.", "orcid": "0000-0002-3856-8385", "clpid": "Herter-T-L" }, { "family_name": "Hora", "given_name": "J. L.", "orcid": "0000-0002-5599-4650", "clpid": "Hora-J-L" }, { "family_name": "Schneider", "given_name": "N.", "clpid": "Schneider-N" }, { "family_name": "Lau", "given_name": "R. M.", "clpid": "Lau-Ryan-M" }, { "family_name": "Staguhn", "given_name": "J. G.", "orcid": "0000-0002-8437-0433", "clpid": "Staguhn-J-G" }, { "family_name": "Simon", "given_name": "R.", "clpid": "Simon-R" }, { "family_name": "Smith", "given_name": "N.", "clpid": "Smith-N-D" }, { "family_name": "Gehrz", "given_name": "R. D.", "orcid": "0000-0003-1319-4089", "clpid": "Gehrz-R-D" }, { "family_name": "Allen", "given_name": "L. E.", "clpid": "Allen-L-E" }, { "family_name": "Bontemps", "given_name": "S.", "clpid": "Bontemps-S" }, { "family_name": "Carey", "given_name": "S. J.", "orcid": "0000-0002-0221-6871", "clpid": "Carey-S-J" }, { "family_name": "Fazio", "given_name": "G. G.", "orcid": "0000-0002-0670-0708", "clpid": "Fazio-G-G" }, { "family_name": "Gutermuth", "given_name": "R. A.", "orcid": "0000-0002-6447-899X", "clpid": "Gutermuth-R-A" }, { "family_name": "Guzman Fernandez", "given_name": "A.", "clpid": "Guzman-Fernandez-A" }, { "family_name": "Hankins", "given_name": "M.", "orcid": "0000-0001-9315-8437", "clpid": "Hankins-M-J" }, { "family_name": "Hill", "given_name": "T.", "clpid": "Hill-T" }, { "family_name": "Keto", "given_name": "E.", "clpid": "Keto-Eric" }, { "family_name": "Koenig", "given_name": "X. P.", "clpid": "Koenig-X-P" }, { "family_name": "Kraemer", "given_name": "K. E.", "clpid": "Kraemer-K-E" }, { "family_name": "Megeath", "given_name": "S. T.", "orcid": "0000-0001-7629-3573", "clpid": "Megeath-S-T" }, { "family_name": "Mizuno", "given_name": "D. R.", "clpid": "Mizuno-D-R" }, { "family_name": "Motte", "given_name": "F.", "clpid": "Motte-F" }, { "family_name": "Myers", "given_name": "P. C.", "clpid": "Myers-P-C" }, { "family_name": "Smith", "given_name": "H. A.", "clpid": "Smith-H-A" } ], "abstract": "We present mid-IR (19\u201337 \u03bcm) imaging observations of S106 from SOFIA/FORCAST, complemented with IR observations from Spitzer/IRAC (3.6\u20138.0 \u03bcm), IRTF/MIRLIN (11.3 and 12.5 \u03bcm), and Herschel/PACS (70 and 160 \u03bcm). We use these observations, observations in the literature, and radiation transfer modeling to study the heating and composition of the warm (~100 K) dust in the region. The dust is heated radiatively by the source S106 IR, with little contributions from grain\u2013electron collisions and Ly\u03b1 radiation. The dust luminosity is \u2273(9.02 \u00b1 1.01) \u00d7 10^4 L_\u2299, consistent with heating by a mid- to late-type O star. We find a temperature gradient (~75\u2013107 K) in the lobes, which is consistent with a dusty equatorial geometry around S106 IR. Furthermore, the SOFIA observations resolve several cool (~65\u201370 K) lanes and pockets of warmer (~75\u201390 K) dust in the ionization shadow, indicating that the environment is fragmented. We model the dust mass as a composition of amorphous silicates, amorphous carbon, big grains, very small grains, and polycyclic aromatic hydrocarbons. We present the relative abundances of each grain component for several locations in S106.", "doi": "10.1088/0004-637X/814/1/54", "issn": "0004-637X", "publisher": "American Astronomical Society", "publication": "Astrophysical Journal", "publication_date": "2015-11-20", "series_number": "1", "volume": "814", "issue": "1", "pages": "Art. No. 54" } ]