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A Search for TeV Emission from X-Ray Selected AGN with Milagro

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Multiwavelength Approach to Unidentified Gamma-Ray Sources
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Abstract

A TeV emission component has been detected from several active galactic nuclei (AGN). The majority of TeV detections of AGN are for nearby (z < 0.13) X-ray selected BL Lacs in flaring states. The variability of these sources makes continuous monitoring necessary to detect flaring activity.

The Milagro gamma-ray observatory is a wide-field (∼2 sr) instrument that operates continuously allowing daily observations of the Northern hemisphere. No significant detections of unidentified sources have been made to date. The observations are used to set limits on the time-integrated behavior of a set of X-ray selected BL Lacs. Costamante and Ghisellini [A&A 384 (2002) 56] present a selection of BL Lacs with X-ray and radio flux levels favorable for TeV emission and make predictions for the TeV flux levels. Twenty-seven objects selected from this sample are the subjects of a search for TeV emission on time scales from 8 days to 2.8 years in data taken between December 15, 2000, and September 8, 2003. None of the selectedBLLacs are detected on any of the time scales. Flux limits will be presented for each galaxy and time scale and comparisons will be made with the predicted emission.

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© 2005 Springer

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Hays, E. (2005). A Search for TeV Emission from X-Ray Selected AGN with Milagro. In: Cheng, K., Romero, G. (eds) Multiwavelength Approach to Unidentified Gamma-Ray Sources. Springer, Dordrecht. https://doi.org/10.1007/1-4020-3881-X_5

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  • DOI: https://doi.org/10.1007/1-4020-3881-X_5

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  • Publisher Name: Springer, Dordrecht

  • Print ISBN: 978-1-4020-3214-1

  • Online ISBN: 978-1-4020-3881-5

  • eBook Packages: Physics and AstronomyPhysics and Astronomy (R0)

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