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Identification of 8 INTEGRAL hard X-ray sources with Chandra

S. Sazonov·E. Churazov·M. Revnivtsev·A. Vikhlinin·R. Sunyaev
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Abstract

We report the results of identification of 8 hard X-ray sources discovered by the INTEGRAL observatory during the ongoing all-sky survey. These sources have been observed by Chandra. In 6 cases a bright X-ray source was found within the INTEGRAL localization region, which permitted to unambigously identify 5 of the objects with nearby galaxies, implying that they have an active galactic nucleus (AGN), whereas one source is likely an X-ray binary in LMC. 4 of the 5 newly discovered AGNs have measured redshifts in the range 0.025-0.055. The X-ray spectra reveal the presence of significant amounts of absorbing gas (NH in the range 10^22-10^24 cm^-2) in all 5 AGNs, demonstrating that INTEGRAL is starting to fill in the sample of nearby obscured AGNs.

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S. Sazonov, E. Churazov, M. Revnivtsev, A. Vikhlinin, R. Sunyaev. 2006-01-02. Identification of 8 INTEGRAL hard X-ray sources with Chandra. https://doi.org/10.1051/0004-6361%3A200500205

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