[SSD2016] 53 , the SIMBAD biblio

We present the results of the analysis of five XMM-Newton observations of the Draco dwarf spheroidal galaxy(dSph). The aim of the work is the study of the X-ray population in the field of the Draco dSph. We classified the sources on the basis of spectral analysis, hardness ratios, X-ray-to-optical flux ratio, X-ray variability, and cross-correlation with available catalogues in X-ray, optical, infrared, and radio wavelengths. We detected 70 X-ray sources in the field of the Draco dSph in the energy range of 0.2-12keV and classified 18 AGNs, 9 galaxies and galaxy candidates, 6 sources as foreground stars, 4 low-mass X-ray binary candidates, 1 symbiotic star, and 2 binary system candidates. We also identified 9 sources as hard X-ray sources in the field of the galaxy. We derived the X-ray luminosity function of X-ray sources in the Draco dSph in the 2-10keV and 0.5-2keV energy bands. Using the X-ray luminosity function in the energy range of 0.5-2keV, we estimate that ∼10 X-ray sources are objects in the Draco dSph. We have also estimated the dark matter halo mass that would be needed tokeep the low-mass X-ray binaries gravitationally bound to the galaxy.