X-ray emission from the giant molecular clouds in the Galactic Center region and the discovery of new X-ray sources

Abstract

We report the results of X{ray (2{10 keV) observations of the giant molecular clouds Sgr B, Sgr C and Sgr D in the Galactic Center region, together with the discovery of the point-like source SAX J1748.2{2808. The data have been obtained with the MECS instrument on the BeppoSAX satellite. The core of Sgr B2 has an X{ray luminosity of6 10 34 erg s 1 and its spectrum is characterized by a strong Fe emission line at6.5 keV with an equivalent width of 2 keV. Faint diuse X{ray emission is detected from Sgr C and from the SNR G1.05{0.15 (Sgr D). A new, unresolved source with a strong Fe line has been discovered in the Sgr D region. This source, SAX J1748.2{2808, is probably associated with a SiO and OH maser source at the Galactic Center distance. If so, its luminosity is 10 34 erg s 1 . We propose that the X{ray emission from SAX J1748.2{2808 is produced either by protostars or by a giant molecular cloud core. Emission from sources similar to SAX J1748.2{2808 could have an impact on the expected contribution on the observed Fe line emission from the Galactic ridge.