Antoranz Canales, PedroContreras González, José LuisFonseca González, María VictoriaLópez Moya, MarcosMiranda Pantoja, José Miguel2023-06-202023-06-202007-110004-636110.1051/0004-6361:20078168https://hdl.handle.net/20.500.14352/50899© ESO 2007. We would like to thank the IAC for the excellent working conditions at the Observatorio del Roque de los Muchachos in La Palma. The support of the German BMBF and MPG, the Italian INFN and the Spanish CICYT is gratefully acknowledged. This work was also supported by ETH Research Grant TH 34/04 3 and the Polish MNiI Grant 1P03D01028.Aims. We searched for very high energy (VHE)gamma-ray emission from the supernova remnant Cassiopeia A. Methods. The shell-type supernova remnant Cassiopeia A was observed with the 17 m MAGIC telescope between July 2006 and January 2007 for a total time of 47 h. Results. The source was detected above an energy of 250 GeV with a significance of 5.2s and a photon flux above 1 TeV of (7.3 +/- 0.7(stat) +/- 2.2(sys)) x 10(-13) cm(-2)s(-1). The photon spectrum is compatible with a power law dN/dE proportional to E-r 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.engjournal articlehttp://dx.doi.org/10.1051/0004-6361:20078168http://www.aanda.orgopen access537539.1Supernova-Remnants5 GHZAccelerationProgenitorEmission.Electrónica (Física)ElectricidadFísica nuclear2202.03 Electricidad2207 Física Atómica y Nuclear