The X-ray emission of contact binaries (EW-type) is an important facet of such systems. Thus, X-ray emitting EW-type binaries (EWXs) are ideal laboratories for studying the X-ray radiation saturation mechanisms as well as binary evolution. By assembling the largest sample to date of EWXs with periods of less than 1 day from the All-Sky Automated Survey for Supernovae Variable Stars Database and X-ray catalogs from the XMM-Newton and ROSAT missions, we aim to conduct a systematic population study of X-ray emission properties of EWXs within 1 kpc. We carried out correlation analyses for the X-ray luminosity, logLX, and X-ray activity level log(LX/Lbol) versus the orbital period, P, effective temperature, Teff, metallicity [Fe/H], and the surface gravity logg of EWXs. We investigated the relation between X-ray emission and the mass of component stars in the binary systems. We also performed sample simulations to explore the degeneracy between period, mass, and effective temperature for EWXs. We find strong P-logLX and P-log(LX/Lbol) correlations for EWXs with P0.44-days.

Cone search capability for table J/A+A/663/A115/table1 (Properties of EWXs in STW (Groups A, B and C))

Cone search capability for table J/A+A/663/A115/table2 (Properties of objects in SRASS)

Cone search capability for table J/A+A/663/A115/table3 (Several parameters of EWXs in Spec-EWX sample)

Cone search capability for table J/A+A/663/A115/table4 (Several parameters of X-ray luminosity upper limits from XMM-Newton pointed and slew surveys for EW-type binaries)

Cone search capability for table J/A+A/663/A115/table5 (Several parameters of X-ray luminosity upper limits from ROSAT survey for EW-type binaries)