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arXiv · astro-ph/9901277

GeV emission from the nearby radio galaxy Centaurus A

P. Sreekumar·D. L. Bertsch·R. C. Hartman·P. L. Nolan·D. J. Thompson
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Abstract

EGRET has detected 67 sources associated with active galactic nuclei. With the exception of radio galaxy Cen A, all are classified as belonging to the blazar class of active galactic nuclei. The cumulative exposure from multiple EGRET observations has provided the first clear detection of Centaurus A. Unlike the \gr blazars seen by EGRET which are believed to exhibit near-alignment of the central jet along the line-of-sight, Cen A provides the first evidence for $>$100 MeV emission from a source with a confirmed large-inclination jet. Although the high-energy emission represents a lower luminosity than most EGRET blazars, with the advent of new more sensitive instruments such as GLAST and VERITAS, the detection of off-axis high-energy emission from more distant radio galaxies is an exciting possibility.

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P. Sreekumar, D. L. Bertsch, R. C. Hartman, P. L. Nolan, D. J. Thompson. 1999-01-20. GeV emission from the nearby radio galaxy Centaurus A. https://doi.org/10.1016/s0927-6505(99)00054-7

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