JEM-X/INTEGRAL X-ray survey of the galactic center region

Abstract

An X-ray survey of the Galactic center region with a radius of ~20° has been performed using the data obtained with the JEM-X telescope onboard the INTEGRAL observatory over ~10 years of observations (2003-2013). The exposure at the field center directly toward the Galactic center has reached 4.8 Ms. We have constructed sky maps in the 5-10 and 10-25 keV energy bands and compiled a catalog of detected sources. Together with 83 sources revealed on the integral sky maps, it includes 22 transients that are absent on them but are confidently detected during outbursts with a duration of several days. One of the persistent sources, IGR J17452-2909, has never been observed previously. In contrast to the catalog of sources detected in the harder energy band by the IBIS/ISGRI telescope onboard the INTEGRAL observatory, most of the sources in this catalog are low-mass X-ray binaries (73 of the 105 sources) and only 18 + 3 are high-mass X-ray binaries and cataclysmic variables. Out of the Galactic sources, there are also the black hole candidate XTE J1652-453, the peculiar X-ray burster XMMJ174457-2850.3, and the soft gamma repeater SGR 1806-20 in the catalog; out of the extragalactic sources, there are three active galactic nuclei and a galaxy cluster (Oph CL). The nature of four sources, including the newly discovered one, still remains unknown. We have constructed the luminosity function for the low-mass X-ray binaries from the catalog and considered other statistical properties of their sample.