42 citations · 181 across the 49 of their papers we have counts for
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The hydrogen-free circumstellar interaction in the Type Ib supernova 2021efd: A clue to the mechanism of the helium-layer stripping
N. Pyykkinen, T. Nagao, H. Kuncarayakti +27
Stripped-envelope supernovae (SESNe), including Type IIb, Ib, and Ic supernovae (SNe), originate from the explosions of massive stars whose outer envelopes have been largely remove…
University of Hawaii 88-inch Telescope Observations of the Interstellar Comet 3I/ATLAS: Spectrophotometric Blue-Sensitive Spectral Time Series Spanning Two Months from Discovery
W. B. Hoogendam, D. Kuesters, B. J. Shappee +22
Interstellar objects are the ejected building blocks of other solar systems. As such, they enable the acquisition of otherwise inaccessible information about nascent extrasolar sys…
The broad-lined type Ic supernova 2020lao experienced an energetic explosion with no central-engine signatures
M. D. Stritzinger, T. J. Moriya, S. Bose +18
We present infant-phase observations of the SN Ic-BL 2020lao, including optical spectroscopy beginning 48 hrs after explosion. The explosion time was constrained by power-law fits…
JCMT Constraints on the Early-Time HCN and CO Emission and HCN Temporal Evolution of 3I/ATLAS
Jason T. Hinkle, Bin Yang, Karen J. Meech +4
Interstellar objects (ISOs), particularly those with cometary activity, provide unique insight into the primordial physical and chemical conditions present during the formation of…
Normal or transitional? The evolution and properties of two type Ia supernovae in the Virgo cluster
L. Izzo, C. Gall, N. Khetan +47
Type Ia supernovae (SNe Ia) are among the most precise cosmological distance indicators used to study the expansion history of the Universe. The vast increase of SN Ia data due to…
The Type Ia Supernova 2021hem: A 2003fg-like Event in an Apparently Hostless Environment
Subhash Bose, M. D. Stritzinger, A. Malmgaard +25
We report observations of Type Ia SN 2021hem, located in an apparently hostless environment. With a peak absolute B-band magnitude of -19.96 mag, and a lack of secondary maximum in…
Characterization of type Ibn SNe
D. Farias, C. Gall, V. A. Villar +29
Type Ibn supernovae (SNe) are characterized by narrow helium (He I) lines from photons produced by the unshocked circumstellar material (CSM). About 80 SNe Ibn have been discovered…
Spectral Diversity in Type Ibn Supernovae and the Large Host Offset of SN2024acyl
Yize Dong, V. Ashley Villar, Anya Nugent +35
In this paper, we first present observations of SN~2024acyl, a normal Type Ibn supernova with a large projected offset (35~kpc) from its host galaxy. The low star-formation r…
Spatial Profiles of 3I/ATLAS CN and Ni Outgassing from Keck/KCWI Integral Field Spectroscopy
W. B. Hoogendam, B. J. Shappee, J. J. Wray +11
Cometary activity from interstellar objects provides a unique window into the environs of other stellar systems. We report blue-sensitive integral field unit spectroscopy of the in…
JWST Observations of SN 2024ggi II: NIRSpec Spectroscopy and CO Modeling at 285 and 385 Days Past the Explosion
T. Mera, C. Ashall, P. Hoeflich +20
We present James Webb Space Telescope (JWST) NIRSpec observations of SN~2024ggi, spanning wavelengths of 1.7--5.5 micron at +285.51 and +385.27 days post-explosion. These nebular s…
Unraveling the Nature of the Nuclear Transient AT2020adpi
Paarmita Pandey, Jason Hinkle, Christopher Kochanek +13
Transient events associated with supermassive black holes provide rare opportunities to study accretion and the environments of supermassive black holes. We present a multiwaveleng…
The nebular phase of SN 2024ggi: a low-mass progenitor with no signs of interaction
L. Ferrari, G. Folatelli, K. Ertini +14
Context: SN 2024ggi is a Type II supernova (SN) discovered in the nearby galaxy NGC 3621 (D Mpc) on 2024 April 03.21 UT. Its proximity enabled a detailed investi…
ASASSN-24fw: An 8-month long, 4.1 mag, optically achromatic and polarized dimming event
R. Forés-Toribio, B. JoHantgen, C. S. Kochanek +20
We discuss ASASSN-24fw, a 13th-magnitude star that optically faded by mag starting in September 2024 after over a decade of quiescence in ASAS-SN. The dimmimg…
The New Status Qvo? SN 2021qvo is Another 2003fg-like Type Ia Supernova with a Rising Light-Curve Bump
I. A. Abreu Paniagua, W. B. Hoogendam, D. O. Jones +24
In recent years, multiple Type Ia supernovae (SNe Ia) have been observed with ''bumps'' in their rising light curves shortly after explosion. Here, we present SN 2021qvo: a SN Ia t…
JWST Observations of SN 2023ixf II: The Panchromatic Evolution Between 250 and 720 Days After the Explosion
K. Medler, C. Ashall, P. Hoeflich +60
We present the nebular phase spectroscopic and photometric observations of the nearby hydrogen-rich core-collapse supernova (CC-SN) 2023ixf, obtained through our JWST programs. The…
Discovery and Preliminary Characterization of a Third Interstellar Object: 3I/ATLAS
Darryl Z. Seligman, Marco Micheli, Davide Farnocchia +44
We report initial observations aimed at the characterization of a third interstellar object. This object, 3I/ATLAS or C/2025 N1 (ATLAS), was discovered on 2025 July 1 UT and has an…
JWST Observations of SN 2023ixf I: Completing the Early Multi-Wavelength Picture with Plateau-phase Spectroscopy
J. M. DerKacy, C. Ashall, E. Baron +46
We present and analyze panchromatic (0.35--14 m) spectroscopy of the Type II supernova 2023ixf, including near- and mid-infrared spectra obtained 33.6 days after explosion durin…
JWST Observations of SN 2024ggi I: Interpretation and Model Comparison of the Type II Supernova 2024ggi at 55 days Past Explosion
E. Baron, C. Ashall, J. M. DerKacy +40
We present panchromatic 0.4-21 microns observations of the nearby (about 7.2 Mpc) Type II supernova 2024ggi, obtained during the plateau phase at about 55 d past explosion. Our dat…
The Hawaii Infrared Supernova Study (HISS): Spectroscopic Data Release 1
K. Medler, C. Ashall, M. Shahbandeh +9
We present the first data release of the Hawaii Infrared Supernova Study (\textit{HISS}), consisting of a large sample of near-infrared (NIR) spectra, , obta…
Early and Extensive Ultraviolet Through Near Infrared Observations of the Intermediate-Luminosity Type Iax Supernovae 2024pxl
W. B. Hoogendam, C. Ashall, D. O. Jones +12
We present ultraviolet (UV) through near-infrared (NIR) photometric and spectroscopic observations of the nearby SN 2024pxl, the third Type Ia supernova (SN Ia) in NGC 6384. SN 202…
The Ultraviolet Spectra of 2003fg-like Type Ia Supernovae
Snehasish Bhattacharjee, Yen-Chen Pan, Hao-Yu Miao +5
2003fg-like Type Ia supernovae (03fg-like SNe Ia) are rare subtype of SNe Ia, photometrically characterized by broader optical light curves and bluer ultraviolet (UV) colors compar…
Seeing the Outer Edge of the Infant Type Ia Supernova 2024epr in the Optical and Near Infrared
W. B. Hoogendam, D. O. Jones, C. Ashall +30
We present optical-to-near-infrared (NIR) photometry and spectroscopy of the Type Ia supernova (SN Ia) 2024epr, including NIR spectra observed within two days of first light. The e…
Rapid follow-up observations of infant supernovae with the Gran Telescopio Canarias
Lluís Galbany, Claudia P. Gutiérrez, Lara Piscarreta +21
The first few hours of a supernova (SN) contain significant information about the progenitor system. The most modern wide-field surveys that scan the sky repeatedly every few days…
Expanding the parameter space of 2002es-like type Ia supernovae: on the underluminous ASASSN-20jq / SN 2020qxp
Subhash Bose, Maximilian D. Stritzinger, Chris Ashall +23
We present optical photometric and spectroscopic observations of the peculiar Type Ia supernova ASASSN-20jq/SN 2020qxp. It is a low-luminosity object with a peak absolute magnitude…