Gravitational collapse as the source of gamma-ray bursts

TL;DR

This paper proposes an alternative compactness solution for gamma-ray bursts, suggesting collimated gamma rays and angle-dependent pair production thresholds could explain GRB observations without requiring ultrarelativistic fireballs.

Contribution

It introduces a novel model where GRBs originate from compact sources with collimated gamma rays, challenging the traditional fireball paradigm.

Findings

A new solution to the compactness problem based on angle-dependent pair production.

GRBs could be linked to core-collapse supernovae without ultrarelativistic jets.

Observational signatures of the compact GRB model are discussed.

Abstract

If the threshold for $e^{-}e^{+}$ pair production depends on an angle between photon momenta, and if the $\gamma$-rays are collimated right in gamma-ray burst (GRB) source then another solution of the compactness problem is possible. The list of basic assumptions of the scenario describing the GRB with energy release $< 10^{49}$ erg is adduced: the matter is about an alternative to the ultrarelativistic fireball if all long-duration GRBs are physically connected with core-collapse supernovae (SNe). The questions about radiation pressure and how the jet arises on account of even a small radiation field asymmetry in a compact GRB source of size $\lesssim 10^8$ cm, and observational consequences of the compact model of GRBs are considered.