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GLAST, GRBs, and Quantum Gravity

J. P. Norris·J. T. Bonnell·G. F. Marani·J. D. Scargle
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Abstract

The fast temporal structures and cosmological distances of gamma-ray bursts (GRBs) afford a natural laboratory for testing theories of frequency-dependent propagation of high-energy photons, as predicted for quantum gravity (QG). We calibrate the sensitivity of the proposed Gamma-ray Large Area Space Telescope (GLAST) by performing simulations which include: the response of GLAST to a GRB fluence distribution; a distribution of spectral power-law indices similar to the EGRET sample; and consideration of gamma-gamma attenuation, significant above ~ 10 GeV for redshifts z > 3 - 5. We find that GLAST should detect > 200 GRBs per year, with sensitivity to a few tens of GeV for a few bursts. GLAST could detect the energy- and distance-dependent dispersion (10 ms / GeV / Gpc) predicted by QG with 1 - 2 years of observations. Attribution to QG would require correlation of GRB redshifts with the temporal and energetic signatures.

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J. P. Norris, J. T. Bonnell, G. F. Marani, J. D. Scargle. 1999-12-07. GLAST, GRBs, and Quantum Gravity. https://arxiv.org/abs/astro-ph/9912136

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