NASA/IPAC EXTRAGALACTIC DATABASE
Date and Time of the Query: 2019-06-27 T05:26:44 PDT
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For refcode 2017ApJ...835..223S:
Retrieve 719 NED objects in this reference.
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NED Abstract

Copyright by American Astronomical Society. Reproduced by permission
2017ApJ...835..223S Chandra Survey of Nearby Galaxies: The Catalog She, Rui; Ho, Luis C.; Feng, Hua Abstract. We searched the public archive of the Chandra X-ray Observatory as of 2016 March and assembled a sample of 719 galaxies within 50 Mpc with available Advanced CCD Imaging Spectrometer observations. By cross-correlation with the optical or near-infrared nuclei of these galaxies, 314 of them are identified to have an X-ray active galactic nucleus (AGN). The majority of them are low-luminosity AGNs and are unlikely X-ray binaries based upon their spatial distribution and luminosity functions. The AGN fraction is around 60% for elliptical galaxies and early-type spirals, but drops to roughly 20% for Sc and later types, consistent with previous findings in the optical. However, the X-ray survey is more powerful in finding weak AGNs, especially from regions with active star formation that may mask the optical AGN signature. For example, 31% of the H II nuclei are found to harbor an X-ray AGN. For most objects, a single power-law model subject to interstellar absorption is adequate to fit the spectrum, and the typical photon index is found to be around 1.8. For galaxies with a non-detection, their stacked Chandra image shows an X-ray excess with a luminosity of a few times 10^37^ erg s^-1^ on average around the nuclear region, possibly composed of faint X-ray binaries. This paper reports on the technique and results of the survey; in-depth analysis and discussion of the results will be reported in forthcoming papers. Key words: galaxies: active, galaxies: nuclei, X-rays: galaxies
Retrieve 719 NED objects in this reference.
Please click here for ADS abstract

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