Observation of VHE gamma-rays from Cassiopeia A with the MAGIC telescope

TL;DR

This paper reports the detection of very high energy gamma-ray emission from the supernova remnant Cassiopeia A using the MAGIC telescope, providing insights into cosmic ray acceleration in such remnants.

Contribution

First detection of VHE gamma-rays from Cassiopeia A with detailed spectral analysis using the MAGIC telescope.

Findings

Detected gamma-ray emission above 250 GeV with 5.2 sigma significance.

Measured photon flux above 1 TeV of (7.3+-0.7_stat+-2.2_sys)×10^-13 cm^-2s^-1.

Photon spectrum follows a power law with index 2.3+-0.2.

Abstract

We searched for very high energy (VHE) gamma-ray emission from the supernova remnant Cassiopeia A. The shell-type supernova remnant Cassiopeia A was observed with the 17 meter MAGIC telescope between July 2006 and January 2007 for a total time of 47 hours. The source was detected above an energy of 250 GeV with a significance of 5.2sigma and a photon flux above 1 TeV of (7.3+-0.7_stat+-2.2_sys)10^-13 cm^-2s^-1. The photon spectrum is compatible with a power law dN/dE = A E^-Gamma with a photon index Gamma=2.3+-0.2_stat+-0.2_sys. The source is point-like within the angular resolution of the telescope.