papers

Publications (35)

astro-ph.CO2026

FlowSN: Neural Simulation-Based Inference under Realistic Selection Effects applied to Supernova Cosmology

Benjamin M. Boyd, Kaisey S. Mandel, Matthew Grayling +10

We present FlowSN, a statistical framework using simulation-based inference (SBI) with normalising flows to account for selection effects in observational astronomy. Failure to acc…

astro-ph.CO2026

The Peculiar Growth of Structure: Validating Measurements from TITAN Type Ia Supernovae and the Uchuu Simulations

Mitchell Dixon, David O. Jones, Nicole E. Drakos +11

The growth rate of cosmic structure, parameterized by , is a fundamental test of CDM and general relativity. Using Type Ia supernova (SN Ia) peculiar velocities in conju…

astro-ph.SR2022

COol Companions ON Ultrawide orbiTS (COCONUTS). III. A Very Red L6 Benchmark Brown Dwarf around a Young M5 Dwarf

Zhoujian Zhang, Michael C. Liu, Caroline V. Morley +5

We present the third discovery from the COol Companions ON Ultrawide orbiTS (COCONUTS) program, the COCONUTS-3 system, composed of a young M5 primary star UCAC4 374-046899 and a ve…

astro-ph.CO2026

On the origin of the environmental step: A BayeSN view of the ZTF SN Ia DR2

Madeleine Ginolin, Matthew Grayling, Kaisey S. Mandel +5

Astrophysical variabilities of Type Ia supernovae (SNe Ia), such as their link with their birth environment, are now one of the leading sources of systematic uncertainties on the m…

astro-ph.HE2026

ATLAS22kjn (AT 2022fpx): A Coronal Line Emitter with an Early Light Curve Bump and Mid-Infrared Dust Echo

Athena C. Engholm, Jason T. Hinkle, Benjamin J. Shappee +14

We present an analysis of ATLAS22kjn (AT 2022fpx), whose high-ionisation coronal lines (CLs) and pre-peak light curve bump provide distinctive opportunities to investigate the phys…

astro-ph.SR2021

Simultaneous Multiwavelength Flare Observations of EV Lacertae

Rishi R. Paudel, Thomas Barclay, Joshua E. Schlieder +17

We present the first results of our ongoing project conducting simultaneous multiwavelength observations of flares on nearby active M dwarfs. We acquired data of the nearby dM3.5e…

astro-ph.SR2020

COol Companions ON Ultrawide orbiTS (COCONUTS). I. A High-Gravity T4 Benchmark around an Old White Dwarf and A Re-Examination of the Surface-Gravity Dependence of the L/T Transition

Zhoujian Zhang, Michael C. Liu, J. J. Hermes +7

We present the first discovery from the COol Companions ON Ultrawide orbiTS (COCONUTS) program, a large-scale survey for wide-orbit planetary and substellar companions. We have dis…

astro-ph.HE2026

AT2021yky: A Fast-Rising Optical Transient with Evolving Broad Hydrogen Emission Consistent with an Ambiguous Nuclear Transient

Paarmita Pandey, Jason T. Hinkle, Christopher Kochanek +14

Nuclear transients are powerful probes of supermassive black hole properties, offering insight into black hole mass, accretion physics, and the structure of galactic nuclei. Among…

astro-ph.HE2025

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…

astro-ph.HE2025

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…

astro-ph.HE2021

Blast From the Past: Constraining Progenitor Models of SN 1972E

Aaron Do, Benjamin J. Shappee, Jean-Pierre De Cuyper +7

We present a novel technique to study Type Ia supernovae by constraining surviving companions of historical extragalactic SN by combining archival photographic plates and Hubble Sp…

astro-ph.CO2026

Hawai`i Supernova Flows: Bulk Flow Measurements using SNe Ia in the Optical and NIR

Aaron Do, Kaisey S. Mandel, Benjamin J. Shappee +9

The present day peculiar velocity-field was sourced by primordial density fluctuations and sculpted over the lifespan of the Universe. Cosmological models such as CDM make pred…

astro-ph.SR2023

An Episode of Occultation Events in Gaia21bcv

Klaus W. Hodapp, Eric Gaidos, Matthew A. Kenworthy +4

A previously unremarkable star near the Canis Major OB1/R1 association underwent an episode of multiple deep brightness minima. Light curves based on archival Gaia, ZTF, NEOWISE da…

astro-ph.HE2024

The Curious Case of ASASSN-20hx: A Slowly-Evolving, UV and X-ray Luminous, Ambiguous Nuclear Transient

Jason T. Hinkle, Thomas W. -S. Holoien, Benjamin. J. Shappee +22

We present observations of ASASSN-20hx, a nearby ambiguous nuclear transient (ANT) discovered in NGC 6297 by the All-Sky Automated Survey for Supernovae (ASAS-SN). We observed ASAS…

astro-ph.SR2024

The Extremely Metal-Poor SN 2023ufx: A Local Analog to High-Redshift Type II Supernovae

Michael A. Tucker, Jason Hinkle, Charlotte R. Angus +26

We present extensive observations of the Type II supernova (SN II) 2023ufx which is likely the most metal-poor SN II observed to-date. It exploded in the outskirts of a low-metalli…

astro-ph.CO2024

The DEHVILS in the Details: Type Ia Supernova Hubble Residual Comparisons and Mass Step Analysis in the Near-Infrared

Erik R. Peterson, Daniel Scolnic, David O. Jones +11

Measurements of Type Ia Supernovae (SNe Ia) in the near-infrared (NIR) have been used both as an alternate path to cosmology compared to optical measurements and as a method of con…

astro-ph.CO2024

Evaluating the Consistency of Cosmological Distances Using Supernova Siblings in the Near-Infrared

Arianna M. Dwomoh, Erik R. Peterson, Daniel Scolnic +7

The study of supernova siblings, supernovae with the same host galaxy, is an important avenue for understanding and measuring the properties of Type Ia Supernova (SN Ia) light curv…

astro-ph.SR2019

WISE J072003.20-084651.2B Is A Massive T Dwarf

Trent J. Dupuy, Michael C. Liu, William M. J. Best +21

We present individual dynamical masses for the nearby M9.5+T5.5 binary WISE J072003.20084651.2AB, a.k.a. Scholz's star. Combining high-precision CFHT/WIRCam photocenter astromet…

astro-ph.IM2025

DAmodel: Hierarchical Bayesian Modelling of DA White Dwarfs for Spectrophotometric Calibration

Benjamin M. Boyd, Gautham Narayan, Kaisey S. Mandel +17

We use hierarchical Bayesian modelling to calibrate a network of 32 all-sky faint DA white dwarf (DA WD) spectrophotometric standards () alongside three CALSPEC st…

astro-ph.CO2023

The DEHVILS Survey Overview and Initial Data Release: High-Quality Near-Infrared Type Ia Supernova Light Curves at Low Redshift

Erik R. Peterson, David O. Jones, Daniel Scolnic +17

While the sample of optical Type Ia Supernova (SN Ia) light curves (LCs) usable for cosmological parameter measurements surpasses 2000, the sample of published, cosmologically viab…

astro-ph.EP2018

Interstellar Interlopers: Number Density and Origins of 'Oumuamua-like Objects

Aaron Do, Michael A. Tucker, John Tonry

We provide a calculation of Pan-STARRS' ability to detect objects similar to the interstellar object 1I/2017 U1 (hereafter 'Oumuamua), including the most detectable approach vector…

astro-ph.HE2021

The Changing Look Blazar B2 1420+32

Hora D. Mishra, Xinyu Dai, Ping Chen +22

Blazars are active galactic nuclei with their relativistic jets pointing toward the observer, with two major sub-classes, the flat spectrum radio quasars and BL Lac objects. We pre…

astro-ph.HE2026

Lightcurve Modelling of 2,205 ZTF DR2 Type~Ia Supernovae: Implications for SN Ia Physics and Cosmology

Nikhil Sarin, Ellen Lindsjö, Lisa Kelsey +11

We fit the multi-band light curves of 2,205 Type Ia supernovae (SNe~Ia) from the Zwicky Transient Facility DR2 with a one-zone radioactive decay model with a phenomenological addit…

astro-ph.HE2021

Late-Onset Circumstellar Medium Interactions are Rare: An Unbiased GALEX View of Type Ia Supernovae

Liam O. Dubay, Michael A. Tucker, Aaron Do +2

Using ultraviolet (UV) light curves we constrain the circumstellar environments of 1080 Type Ia supernovae (SNe Ia) within from archival Galaxy Evolution Explorer (GALEX) o…

astro-ph.CO2026

Characterising the Standardisation Properties of Type Ia Supernovae in the z band with Hierarchical Bayesian Modelling

Erin E. Hayes, Suhail Dhawan, Kaisey S. Mandel +21

Type Ia supernovae (SNe Ia) are standardisable candles: their peak magnitudes can be corrected for correlations between light curve properties and their luminosities to precisely e…

astro-ph.HE2024

Probing the Soft X-ray Properties and Multi-Wavelength Variability of SN2023ixf and its Progenitor

Sonja Panjkov, Katie Auchettl, Benjamin J. Shappee +3

We present a detailed analysis of nearly two decades of optical/UV and X-ray data to study the multi-wavelength pre-explosion properties and post-explosion X-ray properties of near…

astro-ph.SR2020

The Outburst of the Young Star Gaia19bey

Klaus W. Hodapp, Larry Denneau, Michael Tucker +10

We report photometry and spectroscopy of the outburst of the young stellar object Gaia19bey. We have established the outburst light curve with archival Gaia G, ATLAS Orange, ZTF r-…

astro-ph.HE2023

Strong Carbon Features and a Red Early Color in the Underluminous Type Ia SN 2022xkq

Jeniveve Pearson, David J. Sand, Peter Lundqvist +85

We present optical, infrared, ultraviolet, and radio observations of SN 2022xkq, an underluminous fast-declining type Ia supernova (SN Ia) in NGC 1784 ( Mpc),…

astro-ph.HE2024

SCAT Uncovers ATLAS's First Tidal Disruption Event ATLAS18mlw: A Faint and Fast TDE in a Quiescent Balmer Strong Galaxy

Jason T. Hinkle, Michael A. Tucker, Benjamin. J. Shappee +10

We present the discovery that ATLAS18mlw was a tidal disruption event (TDE) in the galaxy WISEA J073544.83+663717.3, at a luminosity distance of 334 Mpc. Initially discovered by th…

astro-ph.HE2025

On the Double: Two Luminous Flares from the Nearby Tidal Disruption Event ASASSN-22ci (AT2022dbl) and Connections to Repeating TDE Candidates

Jason T. Hinkle, Katie Auchettl, Willem B. Hoogendam +16

We present observations of ASASSN-22ci (AT2022dbl), a nearby tidal disruption event (TDE) discovered by the All-Sky Automated Survey for Supernovae (ASAS-SN) at a distance of d$_L…

astro-ph.IM2024

The Multimodal Universe: Enabling Large-Scale Machine Learning with 100TB of Astronomical Scientific Data

The Multimodal Universe Collaboration, Jeroen Audenaert, Micah Bowles +26

We present the MULTIMODAL UNIVERSE, a large-scale multimodal dataset of scientific astronomical data, compiled specifically to facilitate machine learning research. Overall, the MU…

astro-ph.CO2024

Hawai'i Supernova Flows: A Peculiar Velocity Survey Using Over a Thousand Supernovae in the Near-Infrared

Aaron Do, Benjamin J. Shappee, John L. Tonry +15

We introduce the Hawai'i Supernova Flows project and present summary statistics of the first 1,217 astronomical transients observed, 668 of which are spectroscopically classified T…

astro-ph.HE2026

SCAT Data Release 1: 1810 optical spectra of 1330 transients

Michael A. Tucker, Mark E. Huber, Benjamin J. Shappee +18

We present the first data release (DR1) of the Spectroscopic Classification of Astronomical Transients (SCAT) survey, covering the first years of observations (March 20…

astro-ph.HE2026

Supernova Rates and Luminosity Functions from ASAS-SN III: Over a Decade of Type Ia SNe and Their Subtypes

Dhvanil D. Desai, Benjamin J. Shappee, Christopher S. Kochanek +11

We present volumetric rates and luminosity functions (LFs) of Type Ia supernovae (SNe Ia) from the All-Sky Automated Survey for Supernovae (ASAS-SN), covering the 11-year period fr…

astro-ph.HE2025

The Most Energetic Transients: Tidal Disruptions of High-Mass Stars

Jason T. Hinkle, Benjamin J. Shappee, Katie Auchettl +13

We present the class of extreme nuclear transients (ENTs), including the most energetic single transient yet discovered, Gaia18cdj. Each ENT is coincident with its host-galaxy nucl…