2010/06/22 by Fermi-LAT, M. Ackermann, M. Ajello +99 · 30 citations
Physics and Astronomy · #Astronomy and Astrophysical Research #Astrophysics and Cosmic Phenomena #Emission spectrum #Fermi Gamma-ray Space Telescope #Gamma-ray burst #Gamma-ray bursts and supernovae #Observatory #Spectral line #Telescope #astro-ph.HE
paper · pdf · doi:10.1088/2041-8205/717/2/l127
published in The Astrophysical Journal Letters 717(2), L127-L132 (IOP Publishing) · 17 pages, 4 figures. Contact Authors: Fred, Piron; Sara, Cutini; Andreas, von Kienlin
openalex publication_date 2010/06/22 · arxiv created 2010/07/20 · arxiv updated 2010/07/21 · openalex created_date 2019/06/27 · openalex updated_date 2026/08/05
The Fermi observatory is advancing our knowledge of gamma-ray bursts (GRBs) through pioneering observations at high energies, covering more than seven decades in energy with the two on-board detectors, the Large Area Telescope (LAT) and the Gamma-ray Burst Monitor (GBM). Here, we report on the observation of the long GRB 090217A which triggered the GBM and has been detected by the LAT with a significance greater than 9σ. We present the GBM and LAT observations and on-ground analyses, including the time-resolved spectra and the study of the temporal profile from 8 keV up to ∼1 GeV. All spectra are well reproduced by a Band model. We compare these observations to the first two LAT-detected, long bursts GRB 080825C and GRB 080916C. These bursts were found to have time-dependent spectra and exhibited a delayed onset of the high-energy emission, which are not observed in the case of GRB 090217A. We discuss some theoretical implications for the high-energy emission of GRBs.