[
{
"id": "authors:ed9wd-t3z73",
"collection": "authors",
"collection_id": "ed9wd-t3z73",
"cite_using_url": "https://authors.library.caltech.edu/records/ed9wd-t3z73",
"type": "article",
"title": "SN 2021aaev: A Hydrogen-rich Superluminous Supernova with Early Flash and Long-lived Circumstellar Interaction in an Unusual Host Environment",
"author": [
{
"family_name": "Hu \u80e1",
"given_name": "Yang \u9633",
"orcid": "0000-0002-9744-3910"
},
{
"family_name": "Lunnan",
"given_name": "Ragnhild",
"orcid": "0000-0001-9454-4639"
},
{
"family_name": "Pessi",
"given_name": "Priscila J.",
"orcid": "0000-0002-8041-8559"
},
{
"family_name": "Saldana-Lopez",
"given_name": "Alberto",
"orcid": "0000-0001-8419-3062"
},
{
"family_name": "Jerkstrand",
"given_name": "Anders",
"orcid": "0000-0001-8005-4030"
},
{
"family_name": "Sollerman",
"given_name": "Jesper",
"orcid": "0000-0003-1546-6615"
},
{
"family_name": "Schulze",
"given_name": "Steve",
"orcid": "0000-0001-6797-1889"
},
{
"family_name": "Anderson",
"given_name": "Joseph P.",
"orcid": "0000-0003-0227-3451"
},
{
"family_name": "Brennan",
"given_name": "Se\u00e1n J.",
"orcid": "0000-0003-1325-6235"
},
{
"family_name": "Cosentino",
"given_name": "Stefano P.",
"orcid": "0000-0001-8082-5296"
},
{
"family_name": "Gangopadhyay",
"given_name": "Anjasha",
"orcid": "0000-0002-3884-5637"
},
{
"family_name": "Gkini",
"given_name": "Anamaria",
"orcid": "0009-0000-9383-2305"
},
{
"family_name": "Gromadzki",
"given_name": "Mariusz",
"orcid": "0000-0002-1650-1518"
},
{
"family_name": "Hayes",
"given_name": "Matthew J.",
"orcid": "0000-0001-8587-218X"
},
{
"family_name": "Inserra",
"given_name": "Cosimo",
"orcid": "0000-0002-3968-4409"
},
{
"family_name": "M\u00fcller-Bravo",
"given_name": "Tom\u00e1s E.",
"orcid": "0000-0003-3939-7167"
},
{
"family_name": "Nicholl",
"given_name": "Matt",
"orcid": "0000-0002-2555-3192"
},
{
"family_name": "Pignata",
"given_name": "Giuliano",
"orcid": "0000-0003-0006-0188"
},
{
"family_name": "Singh",
"given_name": "Avinash",
"orcid": "0000-0003-2091-622X"
},
{
"family_name": "Wise",
"given_name": "Jacob L.",
"orcid": "0000-0003-0733-2916"
},
{
"family_name": "Yan",
"given_name": "Lin",
"orcid": "0000-0003-1710-9339",
"clpid": "Yan-Lin"
},
{
"family_name": "Adler",
"given_name": "Judy",
"orcid": "0009-0006-7265-2747",
"clpid": "Adler-Judy"
},
{
"family_name": "Chen",
"given_name": "Ting-Wan",
"orcid": "0000-0002-1066-6098"
},
{
"family_name": "Chen",
"given_name": "Tracy X.",
"orcid": "0000-0001-9152-6224",
"clpid": "Chen-Tracy-X"
},
{
"family_name": "Kasliwal",
"given_name": "Mansi M.",
"orcid": "0000-0002-5619-4938",
"clpid": "Kasliwal-M-M"
},
{
"family_name": "Pessi",
"given_name": "Thallis",
"orcid": "0000-0001-6540-0767"
},
{
"family_name": "Salmaso",
"given_name": "Irene",
"orcid": "0000-0003-1450-0869"
},
{
"family_name": "Young",
"given_name": "David R.",
"orcid": "0000-0002-1229-2499"
}
],
"abstract": "We present photometric and spectroscopic observations of SN 2021aaev, a hydrogen-rich, superluminous supernova with persistent (at least ∼100 days) narrow Balmer lines (SLSN-IIn) at redshift z = 0.1557. SN 2021aaev rose over 28.1 ± 1.0 rest-frame days after explosion, reaching a peak absolute magnitude of −21.46 ± 0.01 in the ATLAS o band. The prepeak spectra resemble those of typical Type IIn SNe with flash-ionization features arising from the interaction with a dense, confined circumstellar medium (CSM), albeit the flash timescale is longer than usual (>20 days). Postpeak, the narrow emission lines evolve slowly, and the absence of ejecta features indicates strong deceleration by the CSM. The total radiated energy (about 1.41 × 1051 erg) is possibly explained by a low-mass (1–2 M\u2299) ejecta ploughing into a massive (9–19 M\u2299), extended (outer radius >1 × 1016 cm) H-rich CSM, or alternatively by magnetar-powered models. Interestingly, the host environment consists of a spiral galaxy with a red substructure in the southeastern part, and the SN’s exact location coincides with this quiescent red region (star formation rate = 0.02_(−0.02)^(+0.13) M\u2299 yr−1). Given the atypical environment and the obscuring effect of the massive CSM, a thermonuclear (Type Ia-CSM) origin cannot be ruled out. Altogether, SN 2021aaev is a compelling case to study the diversity of SLSN-IIn features and their host environments.
",
"doi": "10.3847/1538-4357/ae374c",
"issn": "0004-637X",
"publisher": "American Astronomical Society",
"publication": "Astrophysical Journal",
"publication_date": "2026-03-10",
"series_number": "2",
"volume": "999",
"issue": "2",
"pages": "176"
},
{
"id": "authors:10xkv-9sw98",
"collection": "authors",
"collection_id": "10xkv-9sw98",
"cite_using_url": "https://authors.library.caltech.edu/records/10xkv-9sw98",
"type": "article",
"title": "Low-luminosity Type IIP Supernovae from the Zwicky Transient Facility Census of the Local Universe. II. Lightcurve Analysis",
"author": [
{
"family_name": "Das",
"given_name": "Kaustav K.",
"orcid": "0000-0001-8372-997X",
"clpid": "Das-Kaustav-K"
},
{
"family_name": "Kasliwal",
"given_name": "Mansi M.",
"orcid": "0000-0002-5619-4938",
"clpid": "Kasliwal-M-M"
},
{
"family_name": "Sollerman",
"given_name": "Jesper",
"orcid": "0000-0003-1546-6615"
},
{
"family_name": "Fremling",
"given_name": "Christoffer",
"orcid": "0000-0002-4223-103X",
"clpid": "Fremling-Christoffer"
},
{
"family_name": "Moriya",
"given_name": "Takashi J.",
"orcid": "0000-0003-1169-1954"
},
{
"family_name": "Hinds",
"given_name": "K-Ryan",
"orcid": "0000-0002-0129-806X"
},
{
"family_name": "Perley",
"given_name": "Daniel A.",
"orcid": "0000-0001-8472-1996"
},
{
"family_name": "Bellm",
"given_name": "Eric C.",
"orcid": "0000-0001-8018-5348"
},
{
"family_name": "Chen",
"given_name": "Tracy X.",
"orcid": "0000-0001-9152-6224",
"clpid": "Chen-Tracy-X"
},
{
"family_name": "O'Connor",
"given_name": "Evan P.",
"orcid": "0000-0002-8228-796X"
},
{
"family_name": "Coughlin",
"given_name": "Michael W.",
"orcid": "0000-0002-8262-2924"
},
{
"family_name": "Jacobson-Gal\u00e1n",
"given_name": "W. V.",
"orcid": "0000-0002-3934-2644",
"clpid": "Jacobson-Gal\u00e1n-W-V"
},
{
"family_name": "Gangopadhyay",
"given_name": "Anjasha",
"orcid": "0000-0002-3884-5637"
},
{
"family_name": "Graham",
"given_name": "Matthew",
"orcid": "0000-0002-3168-0139",
"clpid": "Graham-M-J"
},
{
"family_name": "Kulkarni",
"given_name": "S. R.",
"orcid": "0000-0001-5390-8563",
"clpid": "Kulkarni-S-R"
},
{
"family_name": "Purdum",
"given_name": "Josiah",
"orcid": "0000-0003-1227-3738",
"clpid": "Purdum-Josiah-N"
},
{
"family_name": "Sarin",
"given_name": "Nikhil",
"orcid": "0000-0003-2700-1030"
},
{
"family_name": "Schulze",
"given_name": "Steve",
"orcid": "0000-0001-6797-1889"
},
{
"family_name": "Singh",
"given_name": "Avinash",
"orcid": "0000-0003-2091-622X"
},
{
"family_name": "Tsuna",
"given_name": "Daichi",
"orcid": "0000-0002-6347-3089",
"clpid": "Tsuna-Daichi"
},
{
"family_name": "Wold",
"given_name": "Avery",
"orcid": "0000-0002-9998-6732",
"clpid": "Wold-Avery"
}
],
"abstract": "The Zwicky Transient Facility Census of the Local Universe survey yielded a sample of 330 Type IIP supernovae (SNe) with well-constrained peak luminosities. In paper I, we measured their luminosity function and volumetric rate. Here (paper II), we present the largest systematic study of lightcurve properties for Type IIP SNe from a volume-limited survey, analyzing a selected subset of 129 events, including 16 low-luminosity Type IIP (LLIIP) SNe with Mr,peak ≥ −16 mag. We find that plateau slope correlates with peak brightness, with many LLIIP SNe showing positive slopes—suggesting smaller progenitor radii and distinct density profiles compared to brighter Type IIP SNe. The plateau duration shows only a weak dependence on peak brightness, likely suggesting binary interaction. One SN exhibits a plateau-to-tail drop of >3.5 mag, consistent with an electron-capture or failed SN with very low or zero nickel mass. We derive explosion and progenitor parameters of the entire Type IIP SN sample using semi-analytical and radiation-hydrodynamical models. Based on radiation-hydrodynamical model fitting, LLIIP SNe are characterized by low nickel masses (0.001–0.025 M\u2299), low explosion energies (0.1–0.28 × 1051 erg), low ejecta masses (8.1_(−1.7)^(+0.8) M\u2299), and ZAMS masses below 11 M\u2299. In comparison, the full Type IIP SN sample spans a wider range with nickel masses (0.001–0.222 M\u2299), explosion energies (0.10-4.43 × 1051 erg), ejecta masses (5.4–24.8 M\u2299), and ZAMS masses (9.3-16.7 M\u2299). We find strong correlations between peak brightness, explosion energy, and nickel mass that extend to the low-luminosity end. We conclude that LLIIP SNe represent the faint, low-energy end of the Type IIP population and originate from the lowest-mass core-collapse progenitors.
",
"doi": "10.1088/1538-3873/ae33f5",
"issn": "0004-6280",
"publisher": "IOP Publishing",
"publication": "Publications of the Astronomical Society of the Pacific",
"publication_date": "2026-02",
"series_number": "2",
"volume": "138",
"issue": "2",
"pages": "024204"
},
{
"id": "authors:t0vsc-k4s10",
"collection": "authors",
"collection_id": "t0vsc-k4s10",
"cite_using_url": "https://authors.library.caltech.edu/records/t0vsc-k4s10",
"type": "article",
"title": "An extremely luminous flare recorded from a supermassive black hole",
"author": [
{
"family_name": "Graham",
"given_name": "Matthew J.",
"orcid": "0000-0002-3168-0139",
"clpid": "Graham-M-J"
},
{
"family_name": "McKernan",
"given_name": "Barry"
},
{
"family_name": "Ford",
"given_name": "K. E. Saavik",
"orcid": "0000-0002-5956-851X"
},
{
"family_name": "Stern",
"given_name": "Daniel",
"orcid": "0000-0003-2686-9241",
"clpid": "Stern-D"
},
{
"family_name": "Cantiello",
"given_name": "Matteo"
},
{
"family_name": "Drake",
"given_name": "Andrew J.",
"clpid": "Drake-Andrew-J"
},
{
"family_name": "Ding",
"given_name": "Yuanze",
"orcid": "0000-0002-5770-2666",
"clpid": "Ding-Yuanze"
},
{
"family_name": "Kasliwal",
"given_name": "Mansi",
"orcid": "0000-0002-5619-4938",
"clpid": "Kasliwal-M-M"
},
{
"family_name": "Koss",
"given_name": "Mike",
"orcid": "0000-0002-7998-9581"
},
{
"family_name": "Margutti",
"given_name": "Raffaella",
"orcid": "0000-0003-4768-7586"
},
{
"family_name": "Rose",
"given_name": "Sam",
"orcid": "0000-0003-4725-4481",
"clpid": "Rose-Sam"
},
{
"family_name": "Somalwar",
"given_name": "Jean",
"orcid": "0000-0001-8426-5732",
"clpid": "Somalwar-Jean-J"
},
{
"family_name": "Wiseman",
"given_name": "Phil"
},
{
"family_name": "Djorgovski",
"given_name": "S. G.",
"orcid": "0000-0002-0603-3087",
"clpid": "Djorgovski-S-G"
},
{
"family_name": "Veres",
"given_name": "Patrik M.",
"orcid": "0000-0002-9553-2987"
},
{
"family_name": "Bellm",
"given_name": "Eric C.",
"orcid": "0000-0001-8018-5348"
},
{
"family_name": "Chen",
"given_name": "Tracy X.",
"orcid": "0000-0001-9152-6224",
"clpid": "Chen-Tracy-X"
},
{
"family_name": "Groom",
"given_name": "Steven L.",
"orcid": "0000-0001-5668-3507",
"clpid": "Groom-Steven-L"
},
{
"family_name": "Kulkarni",
"given_name": "Shrinivas R.",
"orcid": "0000-0001-5390-8563",
"clpid": "Kulkarni-S-R"
},
{
"family_name": "Mahabal",
"given_name": "Ashish",
"orcid": "0000-0003-2242-0244",
"clpid": "Mahabal-A-A"
}
],
"abstract": "\n
\n
Since their discovery more than 60 years ago, accreting supermassive black holes in active galactic nuclei (AGN) have been recognized as highly variable sources, requiring an extremely compact, dynamic environment. Their variability is related to several phenomena, including changing accretion rates, temperature changes, foreground absorbers and structural changes to the accretion disk. Spurred by a new generation of time-domain surveys, the extremes of black hole variability are now being probed. Here we describe the discovery of an extreme flare by the AGN J224554.84+374326.5, which brightened by more than a factor of 40 in 2018. The source has slowly faded since then. The total emitted ultraviolet and optical energy to date is ~1054 erg, which represents the complete conversion of approximately one solar mass into electromagnetic radiation. This flare is 30 times more powerful than the previous most powerful AGN transient. Very few physical events in the Universe can liberate this much electromagnetic energy. We discuss potential mechanisms, including the tidal disruption of a high-mass star (>30 M\u2299), gravitational lensing of an AGN flare or supernova, or a supermassive (pair-instability) supernova in the accretion disk of an AGN. We favour the tidal disruption of a massive star in a prograde orbit in an AGN disk.
\n
\n
\n
On 2025 August 18, the LIGO–Virgo–KAGRA collaboration reported gravitational waves from a subthreshold binary neutron star merger. If astrophysical, this event would have a surprisingly low chirp mass, suggesting that at least one neutron star was below a solar mass. The Zwicky Transient Facility mapped the coarse localization and discovered a transient, ZTF 25abjmnps (AT2025ulz), which was spatially and temporally coincident with the gravitational-wave trigger. The first week of follow-up suggested properties reminiscent of a GW170817-like kilonova. Subsequent follow-up suggests properties most similar to a young, stripped-envelope, Type IIb supernova. Although we cannot statistically rule out chance coincidence, we undertake due diligence analysis to explore the possible association between ZTF 25abjmnps and S250818k. Theoretical models have been proposed wherein subsolar neutron star(s) may form (and subsequently merge) via accretion-disk fragmentation or core fission inside a core-collapse supernova—i.e., a “superkilonova.” Here, we qualitatively discuss our multiwavelength dataset in the context of the superkilonova picture. Future higher-significance gravitational-wave detections of subsolar neutron star mergers with extensive electromagnetic follow-up would conclusively resolve this tantalizing multimessenger association.
\n
We are searching for hot, constant-color, offset optical flares in the Zwicky Transient Facility data stream that are >10″ from any galaxy in public imaging data from the PanSTARRS survey. Here, we present the first discovery from this search: AT 2024puz, a luminous multiwavelength transient offset by 5 kpc from a ∼108 M\u2299 galaxy at z = 0.356 with a low–moderate star formation rate (0.01 ± 0.003 M\u2299 yr−1). It produced luminous 1044.79±0.04 erg s−1 optical/UV emission that evolved on a ∼20 day timescale, as well as 1044.12±0.03 erg s−1 X-ray emission with a photon-index Γ = 1.73_(−0.09)^(+0.10). No associated radio or millimeter emission was detected. We show that the early time optical emission is likely powered by reprocessing of high-energy, accretion-powered radiation, with a possible contribution from a shock in a dense circumtransient medium. If the shock is dominant at early times, the circumtransient medium has a mass ∼0.1–1 M\u2299, a radius 1015 cm, and a density profile shallower than ∼r−1. A near-infrared excess appears at late-times and is suggestive of reprocessing within a wind or other circumtransient medium. The X-rays are most consistent with a central engine. We suggest that AT 2024puz may be associated with an accretion event onto a 50–105 M\u2299 black hole, where the lower masses are preferred based on the large projected offset from the host galaxy. AT2024puz exhibits properties similar to both luminous, fast, blue optical transients and tidal disruption events, but is intermediate between them in its energetics and evolution timescale. This highlights the need for broader exploration of the landscape of hot optical transients to trace their origins.
",
"doi": "10.3847/1538-4357/ae1501",
"issn": "0004-637X",
"publisher": "American Astronomical Society",
"publication": "Astrophysical Journal",
"publication_date": "2025-12-20",
"series_number": "2",
"volume": "995",
"issue": "2",
"pages": "228"
},
{
"id": "authors:024hn-k0f54",
"collection": "authors",
"collection_id": "024hn-k0f54",
"cite_using_url": "https://authors.library.caltech.edu/records/024hn-k0f54",
"type": "article",
"title": "A thermonuclear supernova interacting with hydrogen- and helium-deficient circumstellar material. SN 2020aeuh as a SN Ia-CSM-C/O?",
"author": [
{
"family_name": "Tsalapatas",
"given_name": "K.",
"orcid": "0009-0004-1062-8886"
},
{
"family_name": "Sollerman",
"given_name": "J.",
"orcid": "0000-0003-1546-6615"
},
{
"family_name": "Chiba",
"given_name": "R.",
"orcid": "0009-0003-4594-3715"
},
{
"family_name": "Kool",
"given_name": "E.",
"orcid": "0000-0002-7252-3877"
},
{
"family_name": "Johansson",
"given_name": "J.",
"orcid": "0000-0001-5975-290X"
},
{
"family_name": "Rosswog",
"given_name": "S."
},
{
"family_name": "Schulze",
"given_name": "S.",
"orcid": "0000-0001-6797-1889"
},
{
"family_name": "Moriya",
"given_name": "T. J.",
"orcid": "0000-0003-1169-1954"
},
{
"family_name": "Andreoni",
"given_name": "I.",
"orcid": "0000-0002-8977-1498"
},
{
"family_name": "Brink",
"given_name": "T. G.",
"orcid": "0000-0001-5955-2502"
},
{
"family_name": "Chen",
"given_name": "T. X.",
"orcid": "0000-0001-9152-6224",
"clpid": "Chen-Tracy-X"
},
{
"family_name": "Covarrubias",
"given_name": "S.",
"clpid": "Covarrubias-S"
},
{
"family_name": "De",
"given_name": "K.",
"orcid": "0000-0002-8989-0542"
},
{
"family_name": "Dimitriadis",
"given_name": "G.",
"orcid": "0000-0001-9494-179X"
},
{
"family_name": "Filippenko",
"given_name": "A. V.",
"orcid": "0000-0003-3460-0103"
},
{
"family_name": "Fremling",
"given_name": "C.",
"orcid": "0000-0002-4223-103X",
"clpid": "Fremling-Christoffer"
},
{
"family_name": "Gangopadhyay",
"given_name": "A.",
"orcid": "0000-0002-3884-5637"
},
{
"family_name": "Maguire",
"given_name": "K.",
"orcid": "0000-0002-9770-3508"
},
{
"family_name": "Mo",
"given_name": "G.",
"orcid": "0000-0001-6331-112X"
},
{
"family_name": "Sharma",
"given_name": "Y.",
"orcid": "0000-0003-4531-1745",
"clpid": "Sharma-Yashvi"
},
{
"family_name": "Sravan",
"given_name": "N."
},
{
"family_name": "Terwel",
"given_name": "J. H.",
"orcid": "0000-0001-9834-3439"
},
{
"family_name": "Yang",
"given_name": "Y."
}
],
"abstract": "Identifying the progenitors of thermonuclear supernovae (Type Ia supernovae; SNe Ia) remains a key objective in contemporary astronomy. The rare sub-class of SNe Ia-CSM that interacts with circumstellar material (CSM) allows for studies of the progenitor’s environment before explosion, and generally favours single-degenerate progenitor channels. The case of SN Ia-CSM PTF11kx clearly connected thermonuclear explosions with hydrogen-rich CSM-interacting events, and the more recent SN 2020eyj connected SNe Ia with helium-rich companion progenitors. Both of these objects displayed delayed CSM interaction which established their thermonuclear nature. Here we present a study of SN 2020aeuh, a Type Ia-CSM with delayed interaction. We analyse photometric and spectroscopic data that monitor the evolution of SN 2020aeuh and compare its properties with those of peculiar SNe Ia and core-collapse SNe. At early times, the evolution of SN 2020aeuh resembles a slightly overluminous SN Ia. Later, the interaction-dominated spectra develop the same pseudocontinuum seen in Type Ia-CSM PTF11kx and SN 2020eyj. However, the later-time spectra of SN 2020aeuh lack hydrogen and helium narrow lines. Instead, a few narrow lines could be attributed to carbon and oxygen. We fit the pseudobolometric light curve with a CSM-interaction model, yielding a CSM mass of 1\u2005−\u20052 M\u2299. We propose that SN 2020aeuh was a Type Ia supernova that eventually interacted with a dense medium that was deficient in both hydrogen and helium. Whereas previous SNe Ia-CSM constitute our best evidence of non-degenerate companion progenitors, the CSM around SN 2020aeuh is more difficult to understand. We include a hydrodynamical simulation for a double-degenerate dynamical collision to showcase that such a progenitor scenario could produce significant amounts of hydrogen-poor CSM, although likely not as much as the inferred CSM mass around SN 2020aeuh. It is clear that SN 2020aeuh challenges current models of stellar evolution leading up to a SN Ia explosion.
",
"doi": "10.1051/0004-6361/202556369",
"issn": "0004-6361",
"publisher": "EDP Sciences",
"publication": "Astronomy & Astrophysics",
"publication_date": "2025-12",
"volume": "704",
"pages": "A135"
},
{
"id": "authors:r494d-8jk37",
"collection": "authors",
"collection_id": "r494d-8jk37",
"cite_using_url": "https://authors.library.caltech.edu/records/r494d-8jk37",
"type": "article",
"title": "Prediscovery Activity of New Interstellar Object 3I/ATLAS: Rapid Brightening from 6 to 4 au",
"author": [
{
"family_name": "Ye \u53f6",
"given_name": "Quanzhi \u6cc9\u5fd7",
"orcid": "0000-0002-4838-7676"
},
{
"family_name": "Kelley",
"given_name": "Michael S. P.",
"orcid": "0000-0002-6702-7676"
},
{
"family_name": "Hsieh",
"given_name": "Henry H.",
"orcid": "0000-0001-7225-9271"
},
{
"family_name": "Bellm",
"given_name": "Eric C.",
"orcid": "0000-0001-8018-5348"
},
{
"family_name": "Chen",
"given_name": "Tracy X.",
"orcid": "0000-0001-9152-6224",
"clpid": "Chen-Tracy-X"
},
{
"family_name": "Dekany",
"given_name": "Richard",
"orcid": "0000-0002-5884-7867",
"clpid": "Dekany-Richard"
},
{
"family_name": "Drake",
"given_name": "Andrew",
"orcid": "0000-0003-0228-6594",
"clpid": "Drake-Andrew"
},
{
"family_name": "Groom",
"given_name": "Steven L.",
"orcid": "0000-0001-5668-3507",
"clpid": "Groom-Steven-L"
},
{
"family_name": "Helou",
"given_name": "George",
"orcid": "0000-0003-3367-3415",
"clpid": "Helou-G"
},
{
"family_name": "Kulkarni",
"given_name": "Shrinivas R.",
"orcid": "0000-0001-5390-8563",
"clpid": "Kulkarni-S-R"
},
{
"family_name": "Prince",
"given_name": "Thomas A.",
"orcid": "0000-0002-8850-3627",
"clpid": "Prince-T-A"
},
{
"family_name": "Riddle",
"given_name": "Reed",
"orcid": "0000-0002-0387-370X",
"clpid": "Riddle-Reed"
}
],
"abstract": "We report on the prediscovery observations and constraints of the new interstellar comet 3I/2025 N1 (ATLAS), made by the Zwicky Transient Facility, for the inbound leg of the comet out to a heliocentric distance of rh = 17 au, or approximately a year before its discovery. We find that 3I/ATLAS has been active inward of a heliocentric distance of at least rh = 6.5 au. The comet followed a brightening rate of ∝ r_h^(−3.8), which is significantly steeper than that of the only other known interstellar comet, 2I/Borisov, and is more consistent with dynamically old long-period comets and short-period comets in the solar system. By measuring the brightening of the dust coma, we estimate that 3I had a dust production rate of M_d \u0307 ∼ 5 kg s\u207b¹ in 2025 early May (rh ∼ 6 au), increasing to M_d \u0307 ∼ 5 kg s\u207b¹ toward 2025 mid-July (rh ∼ 4 au) assuming 100 μm dust grains, in line with the more recent Hubble Space Telescope measurement made at rh = 3.8 au. Comparison with the prediscovery photometry by the Transiting Exoplanet Survey Satellite suggested that 3I started producing constant dust outflow probably around rh ∼ 9 au, coinciding with the turn-on distance of CO2 ice. We also conduct a deep search of 3I/ATLAS with multiple nights of data taken in 2024, when the comet was at rh = 13–17 au, and conclude that the comet was no brighter than 2–5 mag above the coma or bare-nucleus lightcurves. This suggests that the comet did not exhibit strong outbursts during these periods, consistent with 2I/Borisov as well as most long-period solar system comets.
",
"doi": "10.3847/2041-8213/ae147b",
"issn": "2041-8205",
"publisher": "American Astronomical Society",
"publication": "Astrophysical Journal Letters",
"publication_date": "2025-11-01",
"series_number": "1",
"volume": "993",
"issue": "1",
"pages": "L31"
},
{
"id": "authors:avkq6-56855",
"collection": "authors",
"collection_id": "avkq6-56855",
"cite_using_url": "https://authors.library.caltech.edu/records/avkq6-56855",
"type": "article",
"title": "A New FU Orionis Accretion Outburst in the W5 H II Region",
"author": [
{
"family_name": "Hillenbrand",
"given_name": "Lynne A.",
"clpid": "Hillenbrand-L-A"
},
{
"family_name": "Graham",
"given_name": "Matthew J.",
"orcid": "0000-0002-3168-0139",
"clpid": "Graham-M-J"
},
{
"family_name": "Kasliwal",
"given_name": "Mansi M.",
"orcid": "0000-0002-5619-4938",
"clpid": "Kasliwal-M-M"
},
{
"family_name": "Purdum",
"given_name": "Josiah",
"orcid": "0000-0003-1227-3738",
"clpid": "Purdum-Josiah"
},
{
"family_name": "Sollerman",
"given_name": "Jesper",
"orcid": "0000-0003-1546-6615"
},
{
"family_name": "Carvalho",
"given_name": "Adolfo S.",
"orcid": "0000-0002-9540-853X"
},
{
"family_name": "Kuhn",
"given_name": "Michael A.",
"orcid": "0000-0002-0631-7514"
},
{
"family_name": "Smith",
"given_name": "Roger",
"orcid": "0000-0001-7062-9726",
"clpid": "Smith-R-M"
},
{
"family_name": "Ashley",
"given_name": "Michael C. B.",
"orcid": "0000-0003-1412-2028"
},
{
"family_name": "Earley",
"given_name": "Nicholas",
"orcid": "0000-0001-6627-9903",
"clpid": "Earley-Nicholas"
},
{
"family_name": "Laher",
"given_name": "Russ R.",
"orcid": "0000-0003-2451-5482",
"clpid": "Laher-R-R"
},
{
"family_name": "Chen",
"given_name": "Tracy X.",
"orcid": "0000-0001-9152-6224",
"clpid": "Chen-Tracy-X"
}
],
"abstract": "\n
We announce a recently detected outburst that is currently only a few months old, and probably of FU Orionis type. The progenitor to the outburst was an emission-line, flat-spectrum spectral energy distribution young stellar object located in the W5 region, though somewhat outside the main star formation action. We present optical, near-infrared, and mid-infrared lightcurves that illustrate the quiescent state of [KAG2008] 13656 and its subsequent Δr ≈ −4 mag and ΔJ ≈ −3 mag outburst over ∼75 days in late-2025. Follow-up optical and near-infrared spectroscopy confirms the expected features from an FU Ori disk and outflow.
\n
Machine learning methods are well established in the classification of quasars (QSOs). However, the advent of light-curve observations adds a great amount of complexity to the problem. Our goal is to use the Zwicky Transient Facility (ZTF) to create a catalog of QSOs. We process the ZTF DR20 light curves with a transformer artificial neural network and combine different surveys with extreme gradient boosting. Based on ZTF g-band and Wide-field Infrared Survey Explorer (WISE) observations, we find 4,849,574 objects classified as QSOs with confidence higher than 90% (QZO). We robustly classify objects fainter than the 5σ signal-to-noise ratio (SNR) limit at g = 20.8 by requiring g < nobs/80 + 20.375. For 33% of QZO objects, with available WISE data, we publish redshifts with estimated error Δz/(1 + z) = 0.14. We find that ZTF classification is superior to the Pan-STARRS static bands, and on par with WISE and Gaia measurements, but the light curves provide the most important features for QSO classification in the ZTF data set. Using ZTF g-band data with at least 100 observational epochs per light curve, we obtain a 97% F1 score for QSOs. We find that with 3 day median cadence, a survey time span of at least 900 days is required to achieve a 90% QSO F1 score. However, one can obtain the same score with a survey time span of 1800 days and the median cadence prolonged to 12 days.
",
"doi": "10.3847/1538-4357/adf4e4",
"issn": "0004-637X",
"publisher": "American Astronomical Society",
"publication": "Astrophysical Journal",
"publication_date": "2025-10-10",
"series_number": "1",
"volume": "992",
"issue": "1",
"pages": "153"
},
{
"id": "authors:mj6ey-k6315",
"collection": "authors",
"collection_id": "mj6ey-k6315",
"cite_using_url": "https://authors.library.caltech.edu/records/mj6ey-k6315",
"type": "article",
"title": "The ambiguous AT2022rze: changing-look AGN mimicking a supernova in a merging galaxy system",
"author": [
{
"family_name": "Pessi",
"given_name": "P J",
"orcid": "0000-0002-8041-8559"
},
{
"family_name": "Lunnan",
"given_name": "R"
},
{
"family_name": "Sollerman",
"given_name": "J",
"orcid": "0000-0003-1546-6615"
},
{
"family_name": "Yan",
"given_name": "L",
"orcid": "0000-0003-1710-9339",
"clpid": "Yan-Lin"
},
{
"family_name": "Le\u00a0Reste",
"given_name": "A",
"orcid": "0000-0003-1767-6421"
},
{
"family_name": "Yao",
"given_name": "Y"
},
{
"family_name": "Nordblom",
"given_name": "S"
},
{
"family_name": "Sharma",
"given_name": "Y",
"orcid": "0000-0003-4531-1745",
"clpid": "Sharma-Yashvi"
},
{
"family_name": "Gilfanov",
"given_name": "M",
"orcid": "0000-0003-4029-6769"
},
{
"family_name": "Sunyaev",
"given_name": "R",
"orcid": "0000-0002-2764-7192"
},
{
"family_name": "Schulze",
"given_name": "S"
},
{
"family_name": "Johansson",
"given_name": "J"
},
{
"family_name": "Gangopadhyay",
"given_name": "A"
},
{
"family_name": "Fremling",
"given_name": "C",
"orcid": "0000-0002-4223-103X",
"clpid": "Fremling-Christoffer"
},
{
"family_name": "Tristram",
"given_name": "K",
"orcid": "0000-0001-8281-5059"
},
{
"family_name": "Hayes",
"given_name": "M J",
"orcid": "0000-0001-8587-218X"
},
{
"family_name": "Fransson",
"given_name": "C"
},
{
"family_name": "Hu",
"given_name": "Y",
"orcid": "0000-0002-9744-3910"
},
{
"family_name": "Brennan",
"given_name": "S J"
},
{
"family_name": "Rose",
"given_name": "S",
"clpid": "Rose-S"
},
{
"family_name": "De",
"given_name": "K",
"orcid": "0000-0002-8989-0542"
},
{
"family_name": "Hinds",
"given_name": "K-R",
"orcid": "0000-0002-0129-806X"
},
{
"family_name": "Liu",
"given_name": "C",
"orcid": "0000-0002-7866-4531"
},
{
"family_name": "Miller",
"given_name": "A A",
"orcid": "0000-0001-9515-478X"
},
{
"family_name": "Qin",
"given_name": "Y-J",
"orcid": "0000-0003-3658-6026",
"clpid": "Qin-Yu-Jing"
},
{
"family_name": "Charalampopoulos",
"given_name": "P",
"orcid": "0000-0002-0326-6715"
},
{
"family_name": "Gkini",
"given_name": "A",
"orcid": "0009-0000-9383-2305"
},
{
"family_name": "Graham",
"given_name": "M J",
"orcid": "0000-0002-3168-0139",
"clpid": "Graham-M-J"
},
{
"family_name": "Guti\u00e9rrez",
"given_name": "C P",
"orcid": "0000-0003-2375-2064"
},
{
"family_name": "Mattila",
"given_name": "S",
"orcid": "0000-0001-7497-2994"
},
{
"family_name": "Nagao",
"given_name": "T",
"orcid": "0000-0002-3933-7861"
},
{
"family_name": "P\u00e9rez-Fournon",
"given_name": "I",
"orcid": "0000-0002-2807-6459"
},
{
"family_name": "Poidevin",
"given_name": "F",
"orcid": "0000-0002-5391-5568"
},
{
"family_name": "Bloom",
"given_name": "J S",
"orcid": "0000-0002-7777-216X"
},
{
"family_name": "Brugger",
"given_name": "J",
"clpid": "Brugger-James"
},
{
"family_name": "Chen",
"given_name": "T X",
"orcid": "0000-0001-9152-6224",
"clpid": "Chen-Tracy-X"
},
{
"family_name": "Kasliwal",
"given_name": "M M",
"orcid": "0000-0002-5619-4938",
"clpid": "Kasliwal-M-M"
},
{
"family_name": "Masci",
"given_name": "F J",
"orcid": "0000-0002-8532-9395",
"clpid": "Masci-Frank-J"
},
{
"family_name": "Purdum",
"given_name": "J N",
"orcid": "0000-0003-1227-3738",
"clpid": "Purdum-Josiah-N"
}
],
"abstract": "AT2022rze is a luminous, ambiguous transient located south-east of the geometric centre of its host galaxy at redshift $z = 0.08$. The host appears to be formed by a merging galaxy system. The observed characteristics of AT2022rze are reminiscent of active galactic nuclei (AGNs), tidal disruption events, and superluminous supernovae. The transient reached a peak absolute magnitude of $-$20.2 $\\pm$ 0.2 mag, showing a sharp rise (t$_{\\mathrm{rise,1/e}} = 27.5 \\pm 0.6$ d) followed by a slow decline (t$_{\\mathrm{dec,1/e}} = 382.9 \\pm 0.6$). Its bumpy light curve and narrow Balmer lines indicate the presence of gas (and dust). Its light curve shows rather red colours, indicating that the transient could be affected by significant host extinction. The spectra reveal coronal lines, indicative of high-energy (X-ray/UV) emission. Archival data reveal no prior activity at this location, disfavouring a steady-state AGN, although an optical spectrum obtained prior to the transient is consistent with an AGN classification of the host. Based on this, we conclude that the transient most likely represents a changing-look AGN at the centre of the smallest component of the merging system.
",
"doi": "10.1093/mnras/staf1433",
"issn": "0035-8711",
"publisher": "Royal Astronomical Society",
"publication": "Monthly Notices of the Royal Astronomical Society",
"publication_date": "2025-10",
"series_number": "4",
"volume": "542",
"issue": "4",
"pages": "3354-3372"
},
{
"id": "authors:p89ah-3x949",
"collection": "authors",
"collection_id": "p89ah-3x949",
"cite_using_url": "https://authors.library.caltech.edu/records/p89ah-3x949",
"type": "article",
"title": "A Luminous Red Optical Flare and Hard X-Ray Emission in the Tidal Disruption Event AT 2024kmq",
"author": [
{
"family_name": "Ho",
"given_name": "Anna Y. Q.",
"orcid": "0000-0002-9017-3567"
},
{
"family_name": "Yao",
"given_name": "Yuhan",
"orcid": "0000-0001-6747-8509"
},
{
"family_name": "Matsumoto",
"given_name": "Tatsuya",
"orcid": "0000-0002-3809-0000"
},
{
"family_name": "Schroeder",
"given_name": "Genevieve",
"orcid": "0000-0001-9915-8147"
},
{
"family_name": "Coughlin",
"given_name": "Eric R.",
"orcid": "0000-0003-3765-6401"
},
{
"family_name": "Perley",
"given_name": "Daniel A.",
"orcid": "0000-0001-8472-1996"
},
{
"family_name": "Andreoni",
"given_name": "Igor",
"orcid": "0000-0002-8977-1498"
},
{
"family_name": "Bellm",
"given_name": "Eric C.",
"orcid": "0000-0001-8018-5348"
},
{
"family_name": "Chen",
"given_name": "Tracy X.",
"orcid": "0000-0001-9152-6224",
"clpid": "Chen-Tracy-X"
},
{
"family_name": "Chornock",
"given_name": "Ryan",
"orcid": "0000-0002-7706-5668"
},
{
"family_name": "Covarrubias",
"given_name": "Sofia",
"orcid": "0000-0003-1858-561X",
"clpid": "Covarrubias-Sofia"
},
{
"family_name": "Das",
"given_name": "Kaustav",
"orcid": "0000-0001-8372-997X",
"clpid": "Das-Kaustav"
},
{
"family_name": "Fremling",
"given_name": "Christoffer",
"orcid": "0000-0002-4223-103X",
"clpid": "Fremling-Christoffer"
},
{
"family_name": "Gilfanov",
"given_name": "Marat"
},
{
"family_name": "Hinds",
"given_name": "K. R.",
"orcid": "0000-0002-0129-806X"
},
{
"family_name": "Jarvis",
"given_name": "Dan",
"orcid": "0009-0004-3067-2227"
},
{
"family_name": "Kasliwal",
"given_name": "Mansi M.",
"orcid": "0000-0002-5619-4938",
"clpid": "Kasliwal-M-M"
},
{
"family_name": "Liu",
"given_name": "Chang",
"orcid": "0000-0002-7866-4531"
},
{
"family_name": "Lyman",
"given_name": "Joseph D.",
"orcid": "0000-0002-3464-0642"
},
{
"family_name": "Masci",
"given_name": "Frank J.",
"orcid": "0000-0002-8532-9395",
"clpid": "Masci-Frank-J"
},
{
"family_name": "Prince",
"given_name": "Thomas A.",
"orcid": "0000-0002-8850-3627",
"clpid": "Prince-T-A"
},
{
"family_name": "Ravi",
"given_name": "Vikram",
"orcid": "0000-0002-7252-5485",
"clpid": "Ravi-Vikram"
},
{
"family_name": "Rich",
"given_name": "R. Michael",
"orcid": "0000-0003-0427-8387"
},
{
"family_name": "Riddle",
"given_name": "Reed",
"orcid": "0000-0002-0387-370X",
"clpid": "Riddle-Reed"
},
{
"family_name": "Sevilla",
"given_name": "Cassie",
"orcid": "0009-0003-2780-704X"
},
{
"family_name": "Smith",
"given_name": "Roger",
"orcid": "0000-0001-7062-9726",
"clpid": "Smith-R-M"
},
{
"family_name": "Sollerman",
"given_name": "Jesper",
"orcid": "0000-0003-1546-6615"
},
{
"family_name": "Somalwar",
"given_name": "Jean J.",
"orcid": "0000-0001-8426-5732",
"clpid": "Somalwar-Jean-J"
},
{
"family_name": "Srinivasaragavan",
"given_name": "Gokul P.",
"orcid": "0000-0002-6428-2700"
},
{
"family_name": "Sunyaev",
"given_name": "Rashid"
},
{
"family_name": "Vail",
"given_name": "Jada L.",
"orcid": "0009-0000-4044-8799"
},
{
"family_name": "Wise",
"given_name": "Jacob L.",
"orcid": "0000-0003-0733-2916"
},
{
"family_name": "Yun",
"given_name": "Sol Bin",
"orcid": "0009-0000-4440-155X",
"clpid": "Yun-Sol-Bin"
}
],
"abstract": "\n
We present the optical discovery and multiwavelength follow-up observations of AT 2024kmq, a likely tidal disruption event (TDE) associated with a supermassive (MBH ∼ 108 M\u2299) black hole in a massive galaxy at z = 0.192. The optical light curve of AT 2024kmq exhibits two distinct peaks: an early fast (timescale 1 day) and luminous (M ≈ −20 mag) red peak, then a slower (timescale 1 month) blue peak with a higher optical luminosity (M ≈ −22 mag) and featureless optical spectra. The second component is similar to the spectroscopic class of “featureless TDEs” in the literature, and during this second component we detect highly variable, luminous (LX ≈ 1044 erg s−1), and hard (fν ∝ ν−1.5) X-ray emission. Luminous (1029 erg s−1 Hz−1 at 10 GHz) but unchanging radio emission likely arises from an underlying active galactic nucleus. The luminosity, timescale, and color of the early red optical peak can be explained by synchrotron emission, or alternatively by thermal emission from material at a large radius (R ≈ a few × 1015 cm). Possible physical origins for this early red component include an off-axis relativistic jet, and shocks from self-intersecting debris leading to the formation of the accretion disk. Late-time radio observations will help distinguish between the two possibilities.
\n
Although all Type II supernovae (SNe) originate from massive stars possessing a hydrogen-rich envelope, their light curve morphology is diverse, reflecting poorly characterised heterogeneity in the physical properties of their progenitor systems. Here, we present a detailed light curve analysis of a magnitude-limited sample of 639 Type II SNe from the Zwicky Transient Facility Bright Transient Survey. Using Gaussian processes, we systematically measure empirical light curve features (e.g. rise times, peak colours and luminosities) in a robust sampling-independent manner. We focus on rise times as they are highly sensitive to pre-explosion progenitor properties, especially the presence of a dense circumstellar medium (CSM) shed by the progenitor in the years immediately pre-explosion. By correlating our feature measurements with physical parameters from an extensive grid of STELLA hydrodynamical models with varying progenitor properties (CSM structure, M, R_(CSM) and M_(ZAMS)), we quantify the proportion of events with sufficient pre-explosion mass-loss to significantly alter the initial light curve (roughly M_(CSM) ≥ 10^(−2.5)M\u2299) in a highly complete sample of 377 spectroscopically classified Type II SNe. We find that 67 ± 6 per cent of observed SNe in our magnitude-limited sample show evidence for substantial CSM (MCSM ≥ 10^(−2.5)M\u2299) close to the progenitor (R_(CSM) < 10¹\u2075 cm) at the time of explosion. After applying a volumetric-correction, we find 36\u207a\u2075\u208b\u2087 per cent of all Type II SN progenitors possess substantial CSM within 10¹\u2075 cm at the time of explosion. This high fraction of progenitors with dense CSM, supported by photometric and spectroscopic evidence of previous SNe, reveals mass-loss rates significantly exceeding those measured in local group red supergiants or predicted by current theoretical models.
",
"doi": "10.1093/mnras/staf888",
"issn": "0035-8711",
"publisher": "Royal Astronomical Society",
"publication": "Monthly Notices of the Royal Astronomical Society",
"publication_date": "2025-07",
"series_number": "1",
"volume": "541",
"issue": "1",
"pages": "135-165"
},
{
"id": "authors:5sgr7-z2p19",
"collection": "authors",
"collection_id": "5sgr7-z2p19",
"cite_using_url": "https://authors.library.caltech.edu/records/5sgr7-z2p19",
"type": "article",
"title": "The BTSbot-nearby Discovery of SN 2024jlf: Rapid, Autonomous Follow-up Probes Interaction in an 18.5 Mpc Type IIP Supernova",
"author": [
{
"family_name": "Rehemtulla",
"given_name": "Nabeel",
"orcid": "0000-0002-5683-2389"
},
{
"family_name": "Jacobson-Gal\u00e1n",
"given_name": "W. V.",
"orcid": "0000-0002-3934-2644",
"clpid": "Jacobson-Gal\u00e1n-W-V"
},
{
"family_name": "Singh",
"given_name": "Avinash",
"orcid": "0000-0003-2091-622X"
},
{
"family_name": "Miller",
"given_name": "Adam A.",
"orcid": "0000-0001-9515-478X"
},
{
"family_name": "Kilpatrick",
"given_name": "Charles D.",
"orcid": "0000-0002-5740-7747"
},
{
"family_name": "Hinds",
"given_name": "K-Ryan",
"orcid": "0000-0002-0129-806X"
},
{
"family_name": "Liu \u5218",
"given_name": "Chang \u7545",
"orcid": "0000-0002-7866-4531"
},
{
"family_name": "Schulze",
"given_name": "Steve",
"orcid": "0000-0001-6797-1889"
},
{
"family_name": "Sollerman",
"given_name": "Jesper",
"orcid": "0000-0003-1546-6615"
},
{
"family_name": "Jegou du Laz",
"given_name": "Theophile",
"orcid": "0009-0003-6181-4526",
"clpid": "Jegou-du-Laz-Theophile"
},
{
"family_name": "Ahumada",
"given_name": "Tom\u00e1s",
"orcid": "0000-0002-2184-6430",
"clpid": "Ahumada-Tom\u00e1s"
},
{
"family_name": "Auchettl",
"given_name": "Katie",
"orcid": "0000-0002-4449-9152"
},
{
"family_name": "Brennan",
"given_name": "S. J.",
"orcid": "0000-0003-1325-6235"
},
{
"family_name": "Coughlin",
"given_name": "Michael W.",
"orcid": "0000-0002-8262-2924"
},
{
"family_name": "Fremling",
"given_name": "Christoffer",
"orcid": "0000-0002-4223-103X",
"clpid": "Fremling-Christoffer"
},
{
"family_name": "Gangopadhyay",
"given_name": "Anjasha",
"orcid": "0000-0002-3884-5637"
},
{
"family_name": "Perley",
"given_name": "Daniel A.",
"orcid": "0000-0001-8472-1996"
},
{
"family_name": "Prusinski",
"given_name": "Nikolaus Z.",
"orcid": "0000-0001-5847-7934",
"clpid": "Prusinski-Nikolaus-Z"
},
{
"family_name": "Purdum",
"given_name": "Josiah",
"orcid": "0000-0003-1227-3738",
"clpid": "Purdum-Josiah"
},
{
"family_name": "Qin",
"given_name": "Yu-Jing",
"orcid": "0000-0003-3658-6026",
"clpid": "Qin-Yu-Jing"
},
{
"family_name": "Romagnoli",
"given_name": "Sara",
"orcid": "0009-0003-8153-9576"
},
{
"family_name": "Shi",
"given_name": "Jennifer",
"orcid": "0009-0008-3724-1824"
},
{
"family_name": "Wise",
"given_name": "Jacob L.",
"orcid": "0000-0003-0733-2916"
},
{
"family_name": "Chen",
"given_name": "Tracy X.",
"orcid": "0000-0001-9152-6224",
"clpid": "Chen-Tracy-X"
},
{
"family_name": "Groom",
"given_name": "Steven L.",
"orcid": "0000-0001-5668-3507",
"clpid": "Groom-Steven-L"
},
{
"family_name": "Jones",
"given_name": "David O.",
"orcid": "0000-0002-6230-0151"
},
{
"family_name": "Kasliwal",
"given_name": "Mansi M.",
"orcid": "0000-0002-5619-4938",
"clpid": "Kasliwal-M-M"
},
{
"family_name": "Smith",
"given_name": "Roger",
"orcid": "0000-0001-7062-9726",
"clpid": "Smith-R-M"
},
{
"family_name": "Sravan",
"given_name": "Niharika"
},
{
"family_name": "Kulkarni",
"given_name": "Shrinivas R.",
"orcid": "0000-0001-5390-8563",
"clpid": "Kulkarni-S-R"
}
],
"abstract": "We present observations of the Type IIP supernova (SN) SN 2024jlf, including spectroscopy beginning just 0.7 days (∼17 hr) after first light. Rapid follow-up was enabled by the new BTSbot-nearby program, which involves autonomously triggering target-of-opportunity requests for new transients in Zwicky Transient Facility data that are coincident with nearby (D < 60 Mpc) galaxies and identified by the BTSbot machine learning model. Early photometry and nondetections shortly prior to first light show that SN 2024jlf initially brightened by >4 mag day−1, quicker than ∼90% of Type II SNe. Early spectra reveal weak flash ionization features: narrow, short-lived (1.3 < τ[days] < 1.8) emission lines of Hα, He ii, and C iv. Assuming a wind velocity of vw = 50 km s−1, these properties indicate that the red supergiant progenitor exhibited enhanced mass loss in the last year before explosion. We constrain the mass-loss rate to 10\u207b\u2074 < M [M\u2299 yr\u207b¹] < 10\u207b³ by matching observations to model grids from two independent radiative hydrodynamics codes. BTSbot-nearby automation minimizes spectroscopic follow-up latency, enabling the observation of ephemeral early-time phenomena exhibited by transients.
",
"doi": "10.3847/1538-4357/adcf1e",
"issn": "0004-637X",
"publisher": "American Astronomical Society",
"publication": "Astrophysical Journal",
"publication_date": "2025-06-01",
"series_number": "2",
"volume": "985",
"issue": "2",
"pages": "241"
},
{
"id": "authors:yn9nt-yns25",
"collection": "authors",
"collection_id": "yn9nt-yns25",
"cite_using_url": "https://authors.library.caltech.edu/records/yn9nt-yns25",
"type": "article",
"title": "ZTF-observed late-time signals of pre-ZTF transients",
"author": [
{
"family_name": "Terwel",
"given_name": "Jacco H.",
"orcid": "0000-0001-9834-3439"
},
{
"family_name": "Maguire",
"given_name": "Kate",
"orcid": "0000-0002-9770-3508"
},
{
"family_name": "Sollerman",
"given_name": "Jesper",
"orcid": "0000-0003-1546-6615"
},
{
"family_name": "Wiseman",
"given_name": "Phil",
"orcid": "0000-0002-3073-1512"
},
{
"family_name": "Chen",
"given_name": "Tracy X.",
"orcid": "0000-0001-9152-6224",
"clpid": "Chen-Tracy-X"
},
{
"family_name": "Graham",
"given_name": "Matthew J.",
"orcid": "0000-0002-3168-0139",
"clpid": "Graham-M-J"
},
{
"family_name": "Laher",
"given_name": "Russ R.",
"orcid": "0000-0003-2451-5482",
"clpid": "Laher-R-R"
},
{
"family_name": "Riddle",
"given_name": "Reed",
"orcid": "0000-0002-0387-370X",
"clpid": "Riddle-Reed"
},
{
"family_name": "Sravan",
"given_name": "Niharika"
}
],
"abstract": "With large-scale surveys such as the Zwicky Transient Facility (ZTF), it has become possible to obtain a well-sampled light curve spanning the full length of the survey for any discovery within the survey footprint. Similarly, any transient within the footprint that was first detected before the start of the survey will likely have a large number of post-transient observations, making such transients excellent targets to search for the presence of late-time signals, particularly those due to interaction with circumstellar material (CSM). We searched for late-time signals in a sample of 7718 transients, mainly supernovae (SNe), that were first detected during the 10 years before the start of ZTF, aiming to find objects showing signs of late-time interaction with CSM. We found one candidate whose late-time signal is best explained by late-time CSM interaction, with the signal being around 300 days after transient discovery. A thin, distant shell containing \u22725 M\u2299 of material could explain the recovered signal. We also found five objects whose late-time signal is best explained by faint nuclear transients occurring in host nuclei close to the pre-ZTF transient locations. Finally, we found two objects where it is difficult to determine whether the signal is from a nuclear transient or due to late-time CSM interaction occurring over 5 years after the SN. This study demonstrates the ability of large-scale surveys to find faint transient signals for a variety of objects and uncover a population of previously unknown sources. However, the large number of non-detections shows that strong late-time CSM interaction occurring years after the SN explosion is extremely rare.
",
"doi": "10.1051/0004-6361/202452198",
"issn": "0004-6361",
"publisher": "EDP Sciences",
"publication": "Astronomy and Astrophysics",
"publication_date": "2025-05",
"volume": "697",
"pages": "A143"
},
{
"id": "authors:qz82n-mwq18",
"collection": "authors",
"collection_id": "qz82n-mwq18",
"cite_using_url": "https://authors.library.caltech.edu/records/qz82n-mwq18",
"type": "article",
"title": "ZTF SN Ia DR2: Overview",
"author": [
{
"family_name": "Rigault",
"given_name": "M.",
"orcid": "0000-0002-8121-2560"
},
{
"family_name": "Smith",
"given_name": "M.",
"orcid": "0000-0002-3321-1432"
},
{
"family_name": "Goobar",
"given_name": "A.",
"orcid": "0000-0002-4163-4996"
},
{
"family_name": "Maguire",
"given_name": "K.",
"orcid": "0000-0002-9770-3508"
},
{
"family_name": "Dimitriadis",
"given_name": "G.",
"orcid": "0000-0001-9494-179X"
},
{
"family_name": "Johansson",
"given_name": "J.",
"orcid": "0000-0001-5975-290X"
},
{
"family_name": "Nordin",
"given_name": "J.",
"orcid": "0000-0001-8342-6274"
},
{
"family_name": "Burgaz",
"given_name": "U.",
"orcid": "0000-0003-0126-3999"
},
{
"family_name": "Dhawan",
"given_name": "S.",
"orcid": "0000-0002-2376-6979"
},
{
"family_name": "Sollerman",
"given_name": "J.",
"orcid": "0000-0003-1546-6615"
},
{
"family_name": "Regnault",
"given_name": "N.",
"orcid": "0000-0001-7029-7901"
},
{
"family_name": "Kowalski",
"given_name": "M.",
"orcid": "0000-0001-8594-8666"
},
{
"family_name": "Nugent",
"given_name": "P.",
"orcid": "0000-0002-3389-0586"
},
{
"family_name": "Andreoni",
"given_name": "I.",
"orcid": "0000-0002-8977-1498"
},
{
"family_name": "Amenouche",
"given_name": "M.",
"orcid": "0009-0006-7454-3579"
},
{
"family_name": "Aubert",
"given_name": "M."
},
{
"family_name": "Barjou-Delayre",
"given_name": "C."
},
{
"family_name": "Bautista",
"given_name": "J.",
"orcid": "0000-0002-9885-3989"
},
{
"family_name": "Bellm",
"given_name": "E.",
"orcid": "0000-0001-8018-5348"
},
{
"family_name": "Betoule",
"given_name": "M.",
"orcid": "0000-0003-0804-836X"
},
{
"family_name": "Bloom",
"given_name": "J. S.",
"orcid": "0000-0002-7777-216X"
},
{
"family_name": "Carreres",
"given_name": "B.",
"orcid": "0000-0002-7234-844X"
},
{
"family_name": "Chen",
"given_name": "T. X.",
"orcid": "0000-0001-9152-6224",
"clpid": "Chen-Tracy-X"
},
{
"family_name": "Copin",
"given_name": "Y.",
"orcid": "0000-0002-5317-7518"
},
{
"family_name": "Deckers",
"given_name": "M.",
"orcid": "0000-0001-8857-9843"
},
{
"family_name": "de Jaeger",
"given_name": "T.",
"orcid": "0000-0001-6069-1139"
},
{
"family_name": "Feinstein",
"given_name": "F.",
"orcid": "0000-0001-5548-3466"
},
{
"family_name": "Fouchez",
"given_name": "D.",
"orcid": "0000-0002-7496-3796"
},
{
"family_name": "Fremling",
"given_name": "C.",
"orcid": "0000-0002-4223-103X",
"clpid": "Fremling-Christoffer"
},
{
"family_name": "Galbany",
"given_name": "L.",
"orcid": "0000-0002-1296-6887"
},
{
"family_name": "Ginolin",
"given_name": "M.",
"orcid": "0009-0004-5311-9301"
},
{
"family_name": "Graham",
"given_name": "M.",
"orcid": "0000-0002-3168-0139",
"clpid": "Graham-M-J"
},
{
"family_name": "Groom",
"given_name": "S. L.",
"orcid": "0000-0001-5668-3507",
"clpid": "Groom-Steven-L"
},
{
"family_name": "Harvey",
"given_name": "L.",
"orcid": "0000-0003-3393-9383"
},
{
"family_name": "Kasliwal",
"given_name": "M. M.",
"orcid": "0000-0002-5619-4938",
"clpid": "Kasliwal-M-M"
},
{
"family_name": "Kenworthy",
"given_name": "W. D.",
"orcid": "0000-0002-5153-5983"
},
{
"family_name": "Kim",
"given_name": "Y.-L.",
"orcid": "0000-0002-1031-0796"
},
{
"family_name": "Kuhn",
"given_name": "D.",
"orcid": "0009-0005-8110-397X"
},
{
"family_name": "Kulkarni",
"given_name": "S. R.",
"orcid": "0000-0001-5390-8563",
"clpid": "Kulkarni-S-R"
},
{
"family_name": "Lacroix",
"given_name": "L.",
"orcid": "0000-0003-0629-5746"
},
{
"family_name": "Laher",
"given_name": "R. R.",
"orcid": "0000-0003-2451-5482",
"clpid": "Laher-R-R"
},
{
"family_name": "Masci",
"given_name": "F. J.",
"orcid": "0000-0002-8532-9395",
"clpid": "Masci-Frank-J"
},
{
"family_name": "M\u00fcller-Bravo",
"given_name": "T. E.",
"orcid": "0000-0003-3939-7167"
},
{
"family_name": "Miller",
"given_name": "A.",
"orcid": "0000-0001-9515-478X"
},
{
"family_name": "Osman",
"given_name": "M.",
"orcid": "0009-0000-6101-6725"
},
{
"family_name": "Perley",
"given_name": "D.",
"orcid": "0000-0001-8472-1996"
},
{
"family_name": "Popovic",
"given_name": "B.",
"orcid": "0000-0002-8012-6978"
},
{
"family_name": "Purdum",
"given_name": "J.",
"orcid": "0000-0003-1227-3738",
"clpid": "Purdum-Josiah"
},
{
"family_name": "Qin",
"given_name": "Y.-J.",
"orcid": "0000-0003-3658-6026",
"clpid": "Qin-Yu-Jing"
},
{
"family_name": "Racine",
"given_name": "B.",
"orcid": "0000-0001-8861-3052"
},
{
"family_name": "Reusch",
"given_name": "S.",
"orcid": "0000-0002-7788-628X"
},
{
"family_name": "Riddle",
"given_name": "R.",
"orcid": "0000-0002-0387-370X",
"clpid": "Riddle-Reed"
},
{
"family_name": "Rosnet",
"given_name": "P.",
"orcid": "0000-0002-6099-7565"
},
{
"family_name": "Rosselli",
"given_name": "D.",
"orcid": "0000-0001-6839-1421"
},
{
"family_name": "Ruppin",
"given_name": "F.",
"orcid": "0000-0002-0955-8954"
},
{
"family_name": "Senzel",
"given_name": "R.",
"orcid": "0009-0002-0243-8199"
},
{
"family_name": "Rusholme",
"given_name": "B.",
"orcid": "0000-0001-7648-4142",
"clpid": "Rusholme-Benjamin"
},
{
"family_name": "Schweyer",
"given_name": "T.",
"orcid": "0000-0001-8948-3456"
},
{
"family_name": "Terwel",
"given_name": "J. H.",
"orcid": "0000-0001-9834-3439"
},
{
"family_name": "Townsend",
"given_name": "A.",
"orcid": "0000-0001-6343-3362"
},
{
"family_name": "Tzanidakis",
"given_name": "A.",
"orcid": "0000-0003-0484-3331"
},
{
"family_name": "Wold",
"given_name": "A.",
"orcid": "0000-0002-9998-6732",
"clpid": "Wold-Avery"
},
{
"family_name": "Yan",
"given_name": "L.",
"orcid": "0000-0003-1710-9339",
"clpid": "Yan-Lin"
}
],
"abstract": "We present the first homogeneous release of several thousand spectroscopically classified type Ia supernovae (SNe Ia) with spectroscopic redshifts. This release, named “DR2”, contains 3628 nearby (z\u2004<\u20040.3) SNe Ia discovered, followed, and classified by the Zwicky Transient Facility survey between March 2018 and December 2020. Of these, 3000 have good-to-excellent sampling and 2667 pass standard cosmology light curve quality cuts. This release is thus the largest SN Ia release to date, increasing by an order of magnitude the number of well-characterized low-redshift objects. With DR2, we also provide a volume-limited (z\u2004<\u20040.06) sample of nearly a thousand SNe Ia. With such a large, homogeneous, and well-controlled dataset, we are studying key current questions on SN cosmology, such as the linearity SNe Ia standardization, the SN and host dependencies, the diversity of the SN Ia population, and the accuracy of current light curve modeling. These, and more, are studied in detail in a series of articles associated with this release. Alongside the SN Ia parameters, we publish our forced-photometry gri-band light curves, 5138 spectra, local and global host properties, observing logs, and a Python tool to facilitate the use and access of these data. The photometric accuracy of DR2 is not yet suited for cosmological parameter inference, which will follow as the “DR2.5” release. We nonetheless demonstrate that our Hubble diagram of several thousands of SNe Ia has a typical 0.15 mag scatter.
",
"doi": "10.1051/0004-6361/202450388",
"issn": "0004-6361",
"publisher": "EDP Sciences",
"publication": "Astronomy and Astrophysics",
"publication_date": "2025-02",
"volume": "694",
"pages": "A1"
},
{
"id": "authors:5gj69-yyr83",
"collection": "authors",
"collection_id": "5gj69-yyr83",
"cite_using_url": "https://authors.library.caltech.edu/records/5gj69-yyr83",
"type": "article",
"title": "A Link Between White Dwarf Pulsars and Polars: Multiwavelength Observations of the 9.36-minute Period Variable Gaia22ayj",
"author": [
{
"family_name": "Rodriguez",
"given_name": "Antonio C.",
"orcid": "0000-0003-4189-9668",
"clpid": "Rodriguez-Antonio-C"
},
{
"family_name": "El-Badry",
"given_name": "Kareem",
"orcid": "0000-0002-6871-1752",
"clpid": "El-Badry-Kareem"
},
{
"family_name": "Hakala",
"given_name": "Pasi",
"orcid": "0009-0003-6437-0369"
},
{
"family_name": "Rodr\u00edguez-Gil",
"given_name": "Pablo",
"orcid": "0000-0002-4717-5102"
},
{
"family_name": "Bao",
"given_name": "Tong",
"orcid": "0000-0002-5082-5049"
},
{
"family_name": "Galiullin",
"given_name": "Ilkham",
"orcid": "0000-0001-5778-2355"
},
{
"family_name": "Kurlander",
"given_name": "Jacob A.",
"orcid": "0009-0005-5452-0671"
},
{
"family_name": "Law",
"given_name": "Casey J.",
"orcid": "0000-0002-4119-9963",
"clpid": "Law-Casey-J"
},
{
"family_name": "Pelisoli",
"given_name": "Ingrid",
"orcid": "0000-0003-4615-6556"
},
{
"family_name": "Schreiber",
"given_name": "Matthias R.",
"orcid": "0000-0003-3903-8009"
},
{
"family_name": "Burdge",
"given_name": "Kevin",
"orcid": "0000-0002-7226-836X"
},
{
"family_name": "Caiazzo",
"given_name": "Ilaria",
"orcid": "0000-0002-4770-5388"
},
{
"family_name": "Roestel",
"given_name": "Jan van",
"orcid": "0000-0002-2626-2872"
},
{
"family_name": "Szkody",
"given_name": "Paula",
"orcid": "0000-0003-4373-7777"
},
{
"family_name": "Drake",
"given_name": "Andrew J.",
"clpid": "Drake-Andrew-J"
},
{
"family_name": "Buckley",
"given_name": "David A. H.",
"orcid": "0000-0002-7004-9956"
},
{
"family_name": "Potter",
"given_name": "Stephen B.",
"orcid": "0000-0002-5956-2249"
},
{
"family_name": "Gaensicke",
"given_name": "Boris",
"orcid": "0000-0002-2761-3005"
},
{
"family_name": "Mori",
"given_name": "Kaya",
"orcid": "0000-0002-9709-5389"
},
{
"family_name": "Bellm",
"given_name": "Eric C.",
"orcid": "0000-0001-8018-5348"
},
{
"family_name": "Kulkarni",
"given_name": "Shrinivas R.",
"orcid": "0000-0001-5390-8563",
"clpid": "Kulkarni-S-R"
},
{
"family_name": "Prince",
"given_name": "Thomas A.",
"orcid": "0000-0002-8850-3627",
"clpid": "Prince-T-A"
},
{
"family_name": "Graham",
"given_name": "Matthew",
"orcid": "0000-0002-3168-0139",
"clpid": "Graham-M-J"
},
{
"family_name": "Kasliwal",
"given_name": "Mansi M.",
"orcid": "0000-0002-5619-4938",
"clpid": "Kasliwal-M-M"
},
{
"family_name": "Rose",
"given_name": "Sam",
"orcid": "0000-0003-4725-4481",
"clpid": "Rose-Sam"
},
{
"family_name": "Sharma",
"given_name": "Yashvi",
"orcid": "0000-0003-4531-1745",
"clpid": "Sharma-Yashvi"
},
{
"family_name": "Ahumada",
"given_name": "Tom\u00e1s",
"orcid": "0000-0002-2184-6430",
"clpid": "Ahumada-Tom\u00e1s"
},
{
"family_name": "Anand",
"given_name": "Shreya",
"orcid": "0000-0003-3768-7515",
"clpid": "Anand-Shreya"
},
{
"family_name": "Viitanen",
"given_name": "Akke",
"orcid": "0000-0001-9383-786X"
},
{
"family_name": "Wold",
"given_name": "Avery",
"orcid": "0000-0002-9998-6732",
"clpid": "Wold-Avery"
},
{
"family_name": "Chen",
"given_name": "Tracy X.",
"orcid": "0000-0001-9152-6224",
"clpid": "Chen-Tracy-X"
},
{
"family_name": "Riddle",
"given_name": "Reed",
"orcid": "0000-0002-0387-370X",
"clpid": "Riddle-Reed"
},
{
"family_name": "Smith",
"given_name": "Roger",
"orcid": "0000-0001-7062-9726",
"clpid": "Smith-R-M"
}
],
"abstract": "White dwarfs (WDs) are the most abundant compact objects, and recent surveys have suggested that over a third of WDs in accreting binaries host a strong (B \u2273 1 MG) magnetic field. However, the origin and evolution of WD magnetism remain under debate. Two WD pulsars, AR Sco and J191213.72–441045.1 (J1912), have been found, which are non-accreting binaries hosting rapidly spinning (1.97 minutes and 5.30 minutes, respectively) magnetic WDs. The WD in AR Sco is slowing down on a P/P\u02d9≈5.6×10\u2076 yr timescale. It is believed they will eventually become polars, accreting systems in which a magnetic WD (B ≈ 10−240 MG) accretes from a Roche lobe-filling donor spinning in sync with the orbit (\u227378 minutes). Here, we present multiwavelength data and analysis of Gaia22ayj, which outbursted in 2022 March. We find that Gaia22ayj is a magnetic accreting WD that is rapidly spinning down (P/P\u02d9=6.1_(−0.2)^(+0.3)×10\u2076 yr) like WD pulsars, but shows clear evidence of accretion, like polars. Strong linear polarization (40%) is detected in Gaia22ayj; such high levels have only been seen in the WD pulsar AR Sco and demonstrate the WD is magnetic. High speed photometry reveals a 9.36 minutes period accompanying a high amplitude (∼2 mag) modulation. We associate this with a WD spin or spin–orbit beat period, not an orbital period as was previously suggested. Fast (60 s) optical spectroscopy reveals a broad \"hump,\" reminiscent of cyclotron emission in polars, between 4000 and 8000 Å. We find an X-ray luminosity of L_X=2.7_(−0.8)^(+6.2)×10³²ergs\u207b¹ in the 0.3–8 keV energy range, while two very large array radio campaigns resulted in a non-detection with a Fr < 15.8 μJy 3σ upper limit. The shared properties of both WD pulsars and polars suggest that Gaia22ayj is a missing link between the two classes of magnetic WD binaries.
",
"doi": "10.1088/1538-3873/adb0f1",
"issn": "0004-6280",
"publisher": "IOP Publishing",
"publication": "Publications of the Astronomical Society of the Pacific",
"publication_date": "2025-02",
"series_number": "2",
"volume": "137",
"issue": "2",
"pages": "024202"
},
{
"id": "authors:ex29t-xd563",
"collection": "authors",
"collection_id": "ex29t-xd563",
"cite_using_url": "https://authors.library.caltech.edu/records/ex29t-xd563",
"type": "article",
"title": "Completeness of the NASA/IPAC Extragalactic Database (NED) Local Volume Sample",
"author": [
{
"family_name": "Cook",
"given_name": "D. O.",
"orcid": "0000-0002-6877-7655",
"clpid": "Cook-David-O"
},
{
"family_name": "Mazzarella",
"given_name": "J. M.",
"orcid": "0000-0002-8204-8619",
"clpid": "Mazzarella-Joseph-M"
},
{
"family_name": "Helou",
"given_name": "G.",
"orcid": "0000-0003-3367-3415",
"clpid": "Helou-G"
},
{
"family_name": "Alcala",
"given_name": "A.",
"clpid": "Alcala-A"
},
{
"family_name": "Chen",
"given_name": "T. X.",
"orcid": "0000-0001-9152-6224",
"clpid": "Chen-Tracy-X"
},
{
"family_name": "Ebert",
"given_name": "R.",
"orcid": "0000-0002-9500-8587",
"clpid": "Ebert-Rick"
},
{
"family_name": "Frayer",
"given_name": "C.",
"clpid": "Frayer-C"
},
{
"family_name": "Kim",
"given_name": "J.",
"clpid": "Kim-J"
},
{
"family_name": "Lo",
"given_name": "T.",
"clpid": "Lo-T"
},
{
"family_name": "Madore",
"given_name": "B. F.",
"orcid": "0000-0002-1576-1676"
},
{
"family_name": "Ogle",
"given_name": "P. M.",
"orcid": "0000-0002-3471-981X"
},
{
"family_name": "Schmitz",
"given_name": "M.",
"orcid": "0000-0002-2055-7549",
"clpid": "Schmitz-Marion"
},
{
"family_name": "Singer",
"given_name": "L. P.",
"orcid": "0000-0001-9898-5597"
},
{
"family_name": "Terek",
"given_name": "S.",
"clpid": "Terek-S"
},
{
"family_name": "Valladon",
"given_name": "J.",
"orcid": "0000-0001-7237-3787"
},
{
"family_name": "Wu",
"given_name": "X.",
"orcid": "0000-0002-4788-9236",
"clpid": "Wu-Xiuqin"
}
],
"abstract": "We introduce the NASA/IPAC Extragalactic Database (NED) Local Volume Sample (NED-LVS), a subset of ∼1.9 million objects with distances out to 1000 Mpc. We use UV and IR fluxes available in NED from all-sky surveys to derive physical properties, and estimate the completeness relative to the expected local luminosity density. The completeness relative to near-IR luminosities (which traces a galaxy's stellar mass) is roughly 100% at D < 30 Mpc and remains moderate (70%) out to 300 Mpc. For brighter galaxies (\u2273L *), NED-LVS is ∼100% complete out to ∼400 Mpc. When compared to other local Universe samples (GLADE and HECATE), all three are ∼100% complete below 30 Mpc. At distances beyond ∼80 Mpc, NED-LVS is more complete than both GLADE and HECATE by ∼10%–20%. NED-LVS is the underlying sample for the NED gravitational-wave follow-up service (NED-GWF), which provides prioritized lists of host candidates for GW events within minutes of alerts issued by the LIGO–Virgo–KAGRA collaboration. We test the prioritization of galaxies in the volume of GW170817 by three physical properties, where we find that both stellar mass and inverse specific star formation rate place the correct host galaxy in the top 10. In addition, NED-LVS can be used for a wide variety of other astrophysical studies: galaxy evolution, star formation, large-scale structure, galaxy environments, and more. The data in NED are updated regularly, and NED-LVS will be updated concurrently. Consequently, NED-LVS will continue to provide an increasingly complete sample of galaxies for a multitude of astrophysical research areas for years to come.
",
"doi": "10.3847/1538-4365/acdd06",
"issn": "0067-0049",
"publisher": "American Astronomical Society",
"publication": "Astrophysical Journal Supplement Series",
"publication_date": "2023-09",
"series_number": "1",
"volume": "268",
"issue": "1",
"pages": "14"
}
]