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Title: GAMMA-RAY BURST PREDICTIONS FOR THE FERMI GAMMA RAY SPACE TELESCOPE

Journal Article · · Astrophysical Journal

Results of a phenomenological model to estimate the gamma-ray burst (GRB) detection rate by the Fermi Gamma-Ray Space Telescope are reported. This estimate is based on the Burst and Transient Source Experiment (BATSE) 4B GRB fluence distribution, the mean ratio of fluences measured at 100 MeV-5 GeV with Energetic Gamma-Ray Experiment Telescope (EGRET) and at 20 keV-2 MeV with BATSE, and the mean EGRET GRB spectrum for the five EGRET spark-chamber GRBs. For a 10% fluence ratio and a number spectral index {alpha}{sub 1} = -2 at 100 MeV- 5 GeV energies, we estimate a rate of {approx}20 and 4 GRBs yr{sup -1} in the Fermi Large Area Telescope field of view (FOV) with at least five photons with energy E>100 MeV and E>1 GeV, respectively. We also estimate {approx}1.5 GRBs yr{sup -1} in the Fermi FOV where at least one photon with energy E>10 GeV is detected. For these parameters, we estimate {approx}1-2 GRBs yr{sup -1} detected with the Fermi telescope with more than 100 {gamma}-rays with E {approx}> 100 MeV. Comparison predictions for {alpha}{sub 1} = -2.2, different fluence ratios, and the AGILE {gamma}-ray satellite are made. Searches for different classes of GRBs using a diagram plotting 100 MeV-10 GeV fluence versus 20 keV- 20 MeV fluence is considered as a way to search for separate classes of GRBs and, specifically, spectral differences between the short-hard and long-duration GRB classes, and for hard components in GRBs.

OSTI ID:
21313815
Journal Information:
Astrophysical Journal, Vol. 700, Issue 2; Other Information: DOI: 10.1088/0004-637X/700/2/1026; Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
Country of Publication:
United States
Language:
English