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We study high mass X-ray binaries (HMXBs) in the Galaxy using data of the INTEGRAL observatory. High sensitivity survey of the whole Galaxy with a possibility to detect absorbed sources significantly enlarged our sample of HMXBs in a comparison with the previous studies. Large fraction of detected high mass X-ray binaries is highly photoabsorbed. We investigated the HMXBs distribution along the Galactic plane and found their strong concentrations toward Galactic spiral arms, confirming previous results of Grimm et al. (2002) obtained using smaller sample of sources. We conclude that the mapping of Galactic HMXBs should be important tool to trace the star formation regions at the opposite side of the Galaxy. [ABSTRACT FROM PUBLISHER]

We analyze in detail the ASCA observations of the hard X-ray source IGR J16318–4848, which was recently discovered by the INTEGRAL observatory (Courvoisier et al. 2003). The source has an anomalously hard spectrum in the energy range 0.5–10 keV and is virtually undetectable below 4 keV because of strong photoabsorption (nHL > 4 × 1023 cm–2). The Kα line of neutral or weakly ionized iron with an equivalent width of ∼2.5 keV dominates in the energy range 4–10 keV. There is also evidence for the presence of a second line at energy ∼7 keV. Our analysis of archival observational data for the infrared counterpart of IGR J16318–4848 that was discovered by Foschini et al. (2003) revealed the source in the wavelength range 1–15 μm. Available data suggest that the object can be an X-ray binary system surrounded by a dense envelope. The source may be a high-mass X-ray binary similar to GX 301-2. We believe that IGR J16318–4848 can be the first representative of a hitherto unknown population of strongly absorbed Galactic X-ray sources that could not be detected by previous X-ray observatories.© 2003 MAIK “Nauka / Interperiodica”. [ABSTRACT FROM AUTHOR]