G. Srinivasaragavan

X-ray Through Radio Observations and Modeling of the Soft X-ray Flash GRB 250419A

Genevieve Schroeder, Anna Y. Q. Ho, Gavin P. Lamb +24

Soft X-ray flashes (XRFs) are predicted from a variety of hypothesized phenomena, including "dirty fireballs" (relativistic jets with significant baryon loading), and gamma-ray bur…

Can We Find the Emission Mechanism Behind the Extremely Bright GRB 230812B?

Utkarsh Pathak, Sameer K. Patil, Hitesh Tanenia +23

GRB 230812B is a bright long-duration GRB with a luminous, long-lived afterglow and an AstroSat/CZTI polarization measurement during the prompt phase, enabling a joint study of its…

A Multi-Wavelength View of the First Type Ic-BL Supernova with an Einstein Probe X-ray Shock Breakout

Jillian C. Rastinejad, Gokul Srinivasaragavan, Nikhil Sarin +36

In March 2026, the Einstein Probe (EP) discovered its most nearby (z = 0.0343) Fast X-ray Transient (FXT), EP260321a, the first EP FXT to provide a strong match to expectations for…

Early Multiwavelength Observations of AT 2026fgk: The Luminous Afterglow to Sub-luminous GRB 260310A, Identified Independently of a Gamma-ray Trigger

K. -R. Hinds, A. Y. Q. Ho, Y. Wagh +103

The origins of sub-luminous ( $L_{γ, iso} < 1 0^{49.5}$ \,erg\,s $^{- 1}$ ) gamma-ray bursts (GRBs) associated with broad-lined Type~Ic supernovae (Ic-BL SNe) are poorly u…

Multiwavelength Analysis of Six Luminous Fast Blue Optical Transients

Cassie Sevilla, Anna Y. Q. Ho, Nayana A. J. +43

We present multiwavelength observations and analysis of six luminous fast blue optical transients (LFBOTs) discovered in Zwicky Transient Facility (ZTF) survey data. We identified…

astro-ph.HE2026★ 4 cited

AT2024wpp: An Extremely Luminous Fast Ultraviolet Transient Powered by Accretion onto a Black Hole

Daniel A. Perley, Anna Y. Q. Ho, Zoë McGrath +69

We present the discovery of AT 2024wpp ("Whippet"), a fast and luminous 18cow-like transient. At a redshift of z=0.0868, revealed by Keck Cosmic Web Imager spectroscopy of its fain…

EP250827b/SN 2025wkm: An X-ray Flash-Supernova Powered by a Central Engine and Circumstellar Interaction

Gokul P. Srinivasaragavan, Dongyue Li, Xander J. Hall +100

We present the discovery of EP250827b/SN 2025wkm, an X-ray Flash (XRF) discovered by the Einstein Probe (EP), accompanied by a broad-line Type Ic supernova (SN Ic-BL) at $z = 0.119…

A search for successful and choked jets in nearby broad-lined Type Ic supernovae

Tanner O'Dwyer, Alessandra Corsi, Sheng Yang +16

The observational link between long gamma-ray bursts (GRBs) and broad-lined stripped-envelope core-collapse supernovae (SNe Ic-BL) is well established. Significant progress has bee…

astro-ph.HE2025★ 1 cited

GRB 250704B: An Off-axis Short GRB with a Long-Lived Afterglow Plateau

Vishwajeet Swain, Tomás Ahumada, Sameer K. Patil +27

We present a detailed multi-wavelength afterglow study of the short GRB 250704B, extensively monitored in optical and near-infrared bands. Its afterglow displays an unusually long-…

SN 2023uqf: An Interacting Supernova Coincident with a High-Energy Neutrino

Robert Stein, Anna Y. Q. Ho, Anjasha Gangopadhyay +30

Astrophysical high-energy (TeV-PeV) neutrinos were first discovered in 2013, but their origin remains largely unknown. Here we present SN 2023uqf, a supernova found in coincidence…

astro-ph.HE2025★ 1 cited

EP250108a/SN 2025kg: A Jet-Driven Stellar Explosion Interacting With Circumstellar Material

Gokul P. Srinivasaragavan, Hamid Hamidani, Genevieve Schroeder +28

We present optical, radio, and X-ray observations of EP250108a/SN 2025kg, a broad-line Type Ic supernova (SN Ic-BL) accompanying an Einstein Probe (EP) fast X-ray transient (FXT) a…

A Luminous Red Optical Flare and Hard X-ray Emission in the Tidal Disruption Event AT2024kmq

Anna Y. Q. Ho, Yuhan Yao, Tatsuya Matsumoto +30

We present the optical discovery and multiwavelength follow-up observations of AT2024kmq, a likely tidal disruption event (TDE) associated with a supermassive ($M_{\rm BH}\sim 10^{…

Multi-Wavelength Analysis of AT 2023sva: a Luminous Orphan Afterglow With Evidence for a Structured Jet

Gokul P. Srinivasaragavan, Daniel A. Perley, Anna Y. Q. Ho +50

We present multi-wavelength analysis of ZTF23abelseb (AT 2023sva), an optically discovered fast-fading ( $Δ m_{r} = 2.2$ mag in $Δ t = 0.74$ days), luminous ( $M_{r} \sim - 30.0$ mag) and…

astro-ph.HE2024★ 1 cited

The Nature of Optical Afterglows Without Gamma-ray Bursts: Identification of AT2023lcr and Multiwavelength Modeling

Maggie L. Li, Anna Y. Q. Ho, Geoffrey Ryan +29

In the past few years, the improved sensitivity and cadence of wide-field optical surveys have enabled the discovery of several afterglows without associated detected gamma-ray bur…

astro-ph.HE2024★ 17 cited

Characterization of a peculiar Einstein Probe transient EP240408a: an exotic gamma-ray burst or an abnormal jetted tidal disruption event?

B. O'Connor, D. Pasham, I. Andreoni +30

We present the results of our multi-wavelength (X-ray to radio) follow-up campaign of the Einstein Probe transient EP240408a. The initial 10 s trigger displayed bright soft X-ray (…

A cosmic formation site of silicon and sulphur revealed by a new type of supernova explosion

Steve Schulze, Avishay Gal-Yam, Luc Dessart +47

The cores of stars are the cosmic furnaces where light elements are fused into heavier nuclei. The fusion of hydrogen to helium initially powers all stars. The ashes of the fusion…

Optical and Radio Analysis of Systematically Classified Broad-lined Type Ic Supernovae from the Zwicky Transient Facility

Gokul P. Srinivasaragavan, Sheng Yang, Shreya Anand +35

We study a magnitude-limited sample of 36 Broad-lined Type Ic Supernovae (SNe Ic-BL) from the Zwicky Transient Facility Bright Transient Survey (detected between March 2018 and Aug…

Multi-Messenger Emission Characteristics of Blazars

Ronald Gamble, Jordan Forman, Amethyst Barnes +3

Multi-Messenger observations and theory of astrophysical objects is fast becoming a critical research area in the astrophysics scientific community. In particular, point-like objec…