Fermi observations of high-energy gamma-ray emission from GRB 080825C

TL;DR

This paper reports on the first firm detection of a gamma-ray burst by the Fermi LAT, analyzing its high-energy emission, temporal and spectral features, and discussing implications for GRB models.

Contribution

It provides the first detailed analysis of a GRB detected simultaneously by Fermi GBM and LAT, including event selection, background estimation, and spectral analysis.

Findings

First firm detection of a GRB by Fermi LAT

Temporal and spectral analysis of GRB 080825C

Insights into high-energy emission mechanisms in GRBs

Abstract

The Fermi Gamma-ray Space Telescope (FGST) has opened a new high-energy window in the study of Gamma-Ray Bursts (GRBs). Here we present a thorough analysis of GRB 080825C, which triggered the Fermi Gamma-ray Burst Monitor (GBM), and was the first firm detection of a GRB by the Fermi Large Area Telescope (LAT). We discuss the LAT event selections, background estimation, significance calculations, and localization for Fermi GRBs in general and GRB 080825C in particular. We show the results of temporal and time-resolved spectral analysis of the GBM and LAT data. We also present some theoretical interpretation of GRB 080825C observations as well as some common features observed in other LAT GRBs.