On the origin of the gamma-ray burst GRB221009A

TL;DR

This paper investigates the origin of the gamma-ray burst GRB221009A, examining its possible connection to supernovae, its high-energy gamma-ray detection, and its likely classification as a giant soft gamma repeater originating within our galaxy.

Contribution

It provides new insights into the nature of GRB221009A, suggesting it is a giant soft gamma repeater rather than a typical cosmological gamma-ray burst.

Findings

GRB221009A is unlikely connected to SN 2022xiw at z=0.151.

Detection of gamma rays up to 18 TeV constrains attenuation at cosmological distances.

GRB221009A is consistent with a giant soft gamma repeater within our galaxy.

Abstract

We analyze a bright and rare burst, GRB20221009A, showing through NED data that the angular distance between GRB221009A and the supernova SN 2022xiw is almost the same angular separation with galactic objects, i.e., the SN-GRB connection at z = 0.151 is not robust. Gamma rays with up to 18 TeV detected in association with the GRB constrain the attenuation to which they are subject at cosmological distances. GR221009A is out of scale relative to other long-lasting GRBs and comes from a region with an excess of soft gamma repeaters (SGR), suggesting that GRB221009A is a giant SGR, with energy release Eiso aproximately 10^{44} erg. The GRBs propagation across the galactic plane reinforces this assumption.