EP260321a is the faintest observed shock breakout tied to a broad-lined Type Ic supernova, interpreted as a choked weak outflow from a stripped star.
iPTF14yb: The First Discovery of a GRB Afterglow Independent of a High-Energy Trigger
2 Pith papers cite this work. Polarity classification is still indexing.
abstract
We report here the discovery by the Intermediate Palomar Transient Factory (iPTF) of iPTF14yb, a luminous ($M_{r}\approx-27.8$ mag), cosmological (redshift 1.9733), rapidly fading optical transient. We demonstrate, based on probabilistic arguments and a comparison with the broader population, that iPTF14yb is the optical afterglow of the long-duration gamma-ray burst GRB 140226A. This marks the first unambiguous discovery of a GRB afterglow prior to (and thus entirely independent of) an associated high-energy trigger. We estimate the rate of iPTF14yb-like sources (i.e., cosmologically distant relativistic explosions) based on iPTF observations, inferring an all-sky value of $\Re_{\mathrm{rel}}=610$ yr$^{-1}$ (68% confidence interval of 110-2000 yr$^{-1}$). Our derived rate is consistent (within the large uncertainty) with the all-sky rate of on-axis GRBs derived by the Swift satellite. Finally, we briefly discuss the implications of the nondetection to date of bona fide "orphan" afterglows (i.e., those lacking detectable high-energy emission) on GRB beaming and the degree of baryon loading in these relativistic jets.
fields
astro-ph.HE 2years
2026 2representative citing papers
First blind optical identification of a z=0.153 sub-luminous GRB afterglow with Ic-BL SN, yielding a volumetric rate consistent with on-axis high-luminosity long GRBs.
citing papers explorer
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EP260321a/SN 2026gzf: The Faintest Shock Breakout Associated with a Broad-Lined Supernova
EP260321a is the faintest observed shock breakout tied to a broad-lined Type Ic supernova, interpreted as a choked weak outflow from a stripped star.
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Early Multiwavelength Observations of AT 2026fgk: The Luminous Afterglow to Sub-luminous GRB 260310A, Identified Independently of a Gamma-ray Trigger
First blind optical identification of a z=0.153 sub-luminous GRB afterglow with Ic-BL SN, yielding a volumetric rate consistent with on-axis high-luminosity long GRBs.