MAGIC upper limits on the high energy emission from GRBs

TL;DR

This paper reports on the MAGIC telescope's observations of nine GRBs during 2005-2006, setting upper limits on their high-energy gamma-ray emission in the 80-200 GeV range, with no detections made.

Contribution

First to provide upper limits on high-energy gamma-ray emission from GRBs using MAGIC telescope data during 2005-2006.

Findings

No gamma-ray emission detected from observed GRBs.

Upper limits are consistent with power law extrapolations.

Attenuation effects due to metagalactic radiation considered.

Abstract

During its cycle-1 observation period, between April 2005 and March 2006, the MAGIC telescope was able to observe nine Gamma Ray Burst (GRB) events since their early beginning. Other observations were performed during the following months in the cycle-2 observation period. The observations, with an energy threshold spanning from 80 to 200 GeV, did not reveal any gamma ray emission. The computed upper limits are compatible with a power law extrapolation, where intrinsic fluxes are evaluated taking into account the attenuation due to the scattering in the metagalactic radiation field.