Observation of Very High Energy $gamma$-Rays from the AGN 1ES 2344+ 514 in a Low Emission State with the MAGIC Telescope
Journal
The Astrophysical Journal 662, 892, 2007
ticlealbert2007observation, title=Observation of Very High Energy $gamma$-Rays from the AGN 1ES 2344+ 514 in a Low Emission State with the MAGIC Telescope, author=Albert, J and Aliu, E and Anderhub, H and Antoranz, P and Armada, A and Baixeras, C and Barr
Abstract:
The MAGIC collaboration has observed very high energy gamma ray emission from the AGN 1ES 2344+514. A gamma-ray signal corresponding to an 11 sigma excess and an integral flux of (2.38+-0.30(stat)+-0.70(syst))*10^-11 cm^-2 s^-1 above 200 GeV has been obtained from 23.1 hours of data taking between 2005 August 3 and 2006 January 1. The data confirm the previously detected gamma-ray emission from this object during a flare seen by the Whipple collaboration in 1995 and the evidence (below 5 sigma significance level) from long-term observations conducted by the Whipple and HEGRA groups. The MAGIC observations show a relatively steep differential photon spectrum that can be described by a power law with a photon index of alpha=-2.95+-0.12(stat)+-0.2(syst) between 140 GeV and 5.4 TeV. The observations reveal a low flux state, about six times below the 1995 flare seen by Whipple and comparable with the previous Whipple and HEGRA long term measurements. During the MAGIC observations no significant time variability has been observed.