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arXiv · astro-ph/9904393

The Zoo of X-ray sources in the Galactic Center Region: Observations with BeppoSAX

Abstract

We report the results of a survey of the Galactic Center region (|l| < 2deg, |b| < 0.5deg) performed with the BeppoSAX satellite. The flux from the center of our Galaxy corresponds to a luminosity of ~3 10^{35} erg/s in the 2-10 keV range. Due to the limited angular resolution ($\gsim 1'$) only part of it is supposed to come from Sagittarius A*, the non-thermal radio source which is believed to mark the dynamical center of the Galaxy. In addition to the diffuse emission, several bright (L$_X\gsim10^{36} ergs/s) point sources have been observed, both persistent (A 1742-294, SLX 1744-299, SLX 1744-300, 1E 1743.1-2843, 1E 1740.7-2942) and transient (XTE J1748-288, SAX J1747.0-2853 and KS 1741-293). The Low Mass X-ray Binary AX J1745.6-2901, discovered with ASCA at only $1.3'$ from SgrA* was detected in a low luminosity state in August 1997. Two fainter sources are very likely associated with young neutron stars: the (possibly diffuse) X-ray source at the center of the composite supernova remnant G0.9+0.1, and the "head" of the axially symmetric radio source G359.23-0.92. The latter has been detected above 6 keV, supporting a non-thermal emission mechanism.

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BibTeXRIS

L. Sidoli, S. Mereghetti, G. L. Israel, L. Chiappetti, A. Treves, M. Orlandini. 1999-04-28. The Zoo of X-ray sources in the Galactic Center Region: Observations with BeppoSAX. https://doi.org/10.1086/307887

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