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Date and Time of the Query: 2019-06-19 T23:28:35 PDT
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For refcode 2002ApJS..143...25C:
Retrieve 139 NED objects in this reference.
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Copyright by American Astronomical Society. Reproduced by permission
2002ApJS..143...25C A Catalog of Candidate Intermediate-Luminosity X-Ray Objects E. J. M. Colbert and A. F. Ptak Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218 Received 2002 March 29; accepted 2002 June 25 ABSTRACT ROSAT, and now Chandra, X-ray images allow studies of extranuclear X-ray point sources in galaxies other than our own. X-ray observations of normal galaxies with ROSAT and Chandra have revealed that off-nuclear, compact, intermediate-luminosity (L_X_[2-10 keV] >= 10^39.0^ ergs s^-1^) X-ray objects (IXOs, a.k.a. ULXs [ultraluminous X-ray sources]) are quite common. Here we present a catalog and finding charts for 87 IXOs in 54 galaxies, derived from all of the ROSAT HRI imaging data for galaxies with cz <= 5000 km s^-1^ from the Third Reference Catalog of Bright Galaxies. We have defined the cutoff LX for IXOs so that it is well above the Eddington luminosity of a 1.4 M_sun_ black hole (10^38.3^ ergs s^-1^), so as not to confuse IXOs with "normal" black hole X-ray binaries. This catalog is intended to provide a baseline for follow-up work with Chandra and XMM-Newton, and with space- and ground-based survey work at wavelengths other than X-ray. We demonstrate that elliptical galaxies with IXOs have a larger number of IXOs per galaxy than nonelliptical galaxies with IXOs and note that they are not likely to be merely high-mass X-ray binaries with beamed X-ray emission, as may be the case for IXOs in starburst galaxies. Approximately half of the IXOs with multiple observations show X-ray variability, and many (19) of the IXOs have faint optical counterparts in DSS optical B-band images. Follow-up observations of these objects should be helpful in identifying their nature. Subject headings: catalogs - galaxies: general - X-rays: binaries - X-rays: galaxies
Retrieve 139 NED objects in this reference.
Please click here for ADS abstract

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