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VHE Gamma Rays from PKS 2155-304

P. M. Chadwick·K. Lyons·T. J. L. McComb·K. J. Orford·J. L. Osborne·S. M. Rayner·S. E. Shaw·K. E. Turver
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Abstract

The X-ray selected BL Lac PKS 2155-304 has been observed using the University of Durham Mark 6 very high energy gamma ray telescope during 1998. We find no evidence for TeV emission during these recent observations when the X-ray flux was observed to be low. We have reconsidered our measurements made in 1997 November when PKS 2155-304 was in a bright X-ray state and extended X-ray and GeV gamma ray observations were made as part of a multiwavelength campaign. Comparisons are made of the VHE emission during this time with the available data from other wavelengths.

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P. M. Chadwick, K. Lyons, T. J. L. McComb, K. J. Orford, J. L. Osborne, S. M. Rayner, S. E. Shaw, K. E. Turver. 1999-06-08. VHE Gamma Rays from PKS 2155-304. https://arxiv.org/abs/astro-ph/9906132

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