Gamma-ray Burst Theory in the Fermi Era

TL;DR

This paper reviews how Fermi's LAT observations of gamma-ray bursts, especially the delayed high-energy emission in bright bursts, impact theoretical models and emphasizes the need for multi-telescope collaboration.

Contribution

It provides a comprehensive analysis of LAT data implications on GRB models and highlights the importance of combined observations for understanding GRB mechanisms.

Findings

LAT detects high-energy emission in a small fraction of bright GRBs

High-energy LAT emission is often delayed relative to lower-energy detection

Synergy between Fermi and other telescopes is crucial for GRB studies

Abstract

The Large Area Telescope (LAT) on-board the Fermi satellite detected emission above 20 MeV only in a small fraction of the long gamma-ray bursts (GRBs) detected by the Fermi Gamma-ray Burst Monitor (GBM) at 8 keV-40 MeV. Those bursts that were detected by the LAT were among the brightest GBM bursts. The emission detected by LAT seerms to be delayed respect to the one detected by the GBM. In this review I will show the main implications of these LAT observations on the GRB models and discuss the importance of a synergy between Fermi and other telescopes.