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arXiv · astro-ph/0209194

STACEE Observations of Markarian 421 During an Extended Gamma-Ray Outburst

STACEE Collaboration·L. M. Boone·J. A. Hinton·D. Bramel·E. Chae·C. E. Covault·P. Fortin·D. M. Gingrich·D. S. Hanna·R. Mukherjee·C. Mueller·R. A. Ong·K. Ragan·R. A. Scalzo·D. R. Schuette·C. G. Theoret·D. A. Williams
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Abstract

The active galaxy Markarian 421 underwent a substantial outburst in early 2001. Between January and May of that year, the STACEE detector was used to observe the source in gamma-rays between the energies of 50 and 500 GeV. These observations represent the lowest energy gamma-ray detection of this outburst by a ground-based experiment. Here we present results from these observations, which indicate an average integral gamma-ray flux of (8.0 +/- 0.7 +/- 1.5)x10^-10 1/cm^2/s. above 140 GeV. We also present a light curve for Markarian 421 as observed by STACEE from March to May, and compare our temporal, as well as spectral, measurements to those of other experiments.

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STACEE Collaboration, L. M. Boone, J. A. Hinton, D. Bramel, E. Chae, C. E. Covault, P. Fortin, D. M. Gingrich, D. S. Hanna, R. Mukherjee, C. Mueller, R. A. Ong, K. Ragan, R. A. Scalzo, D. R. Schuette, C. G. Theoret, D. A. Williams. 2002-09-10. STACEE Observations of Markarian 421 During an Extended Gamma-Ray Outburst. https://doi.org/10.1086/344815

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