XMM-Newton study of the Sculptor dwarf spheroidal galaxy
  We analysed observations with XMM-Newton in the field of the Sculptor dwarf
spheroidal galaxy (dSph). The aim of the study was the classification of X-ray
binaries and accreting white dwarfs, which belong to the Sculptor dSph. Using
different methods of X-ray timing and spectral analyses, together with an
extensive multi-wavelength study of the optical and infrared counterparts of
the X-ray sources, we classified the sources detected with XMM-Newton in the
field of Sculptor dSph. The long term variability of the sources has been
studied over two \xmm\, observations. None of the members of Sculptor dSph show
a significant long-term variability over these two observations. We also
searched for periodicity and pulsation using the Lomb-Scargle and Rayleigh's
Z_n^2 techniques. No signal of pulsation or periodicity have been found for the
X-ray sources. The results show the presence of a noticeable number of
background X-ray sources in the field of this galaxy. We classified 43 sources
as active galactic nuclei (AGNs), galaxies, and galaxy candidates. Three
Galactic foreground stars have been identified in the field of Sculptor dSph,
and one of them is an M-dwarf candidate. Moreover, we classified four symbiotic
star candidates and three quiescent low-mass X-ray binary candidates in
Sculptor dSph. The luminosity of these X-ray sources is 10^{33-35} erg/s.
