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arXiv · 0910.2134

Is the Gamma Ray Bursts emission suppressed at high energy?

Dafne Guetta·Elena Pian
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Abstract

We compare the luminosity function and rate inferred from the GBM long bursts peak flux distribution with those inferred from the Swift and BATSE peak flux distribution. We find that the GBM, BATSE and the Swift peak fluxes can be fitted by the same luminosity function implying the consistency of these three samples. Using the trigger algorithm of the LAT instrument we derive important information on the flux at 100 MeV compared to lower energy detected by the GBM. We find that the simple extension of the synchrotron emission to high energy cannot justify the low rate of GRBs detected by LAT and for several GRBs detected by the GBM, the flux at >100 MeV should be suppressed. Two bursts, GRB090217 and GRB 090202B, detected by LAT have very soft spectra in the GBM and therefore their high energy emission cannot be due to an extension of the synchrotron.

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Dafne Guetta, Elena Pian. 2009-11-05. Is the Gamma Ray Bursts emission suppressed at high energy?. https://arxiv.org/abs/0910.2134

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