Population of the Galactic X-ray binaries and eRosita

TL;DR

This paper reviews current knowledge of Galactic X-ray binary populations, improves luminosity function constraints using INTEGRAL data, and estimates new detections expected from the eRosita all-sky survey.

Contribution

It provides updated X-ray luminosity functions for X-ray binaries and predicts the number of new detections eRosita will achieve.

Findings

Improved constraints on X-ray binary luminosity functions.

Estimated detection of hundreds of new X-ray binaries with eRosita.

Enhanced understanding of low-luminosity X-ray binary populations.

Abstract

The population of the Galactic X-ray binaries has been mostly probed with moderately sensitive hard X-ray surveys so far. The eRosita mission will provide, for the first time a sensitive all-sky X-ray survey in the 2-10 keV energy range, where the X-ray binaries emit most of the flux and discover the still unobserved low-luminosity population of these objects. In this paper, we briefly review the current constraints for the X-ray luminosity functions of high- and low-mass X-ray binaries and present our own analysis based the INTEGRAL 9-year Galactic survey, which yields improved constraints. Based on these results, we estimate the number of new XRBs to be detected in the eRosita all-sky survey