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arXiv · 0709.4598

Upper Limits from HESS Observations of AGN in 2005-2007

Abstract

Very high energy (VHE; >100 GeV) observations of a sample of selected active galactic nuclei (AGN) were performed between January 2005 and April 2007 with the High Energy Stereoscopic System (HESS), an array of imaging atmospheric-Cherenkov telescopes. Significant detections are reported elsewhere for many of these objects. Here, integral flux upper limits for twelve candidate very high energy (VHE; >100 GeV) gamma-ray emitters are presented. In addition, results from HESS observations of four known VHE-bright AGN are given although no significant signal is measured. For three of these AGN (1ES 1101-232, 1ES 1218+304, and Mkn 501) simultaneous data were taken with the Suzaku X-ray satellite.

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HESS Collaboration, W. Benbow, R. Buehler. 2007-09-28. Upper Limits from HESS Observations of AGN in 2005-2007. https://arxiv.org/abs/0709.4598

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