The X‐Ray Binary Population in M33. I. Source List and Luminosity Function

In this paper we present the source list for 3 Chandra observations of theLocal Group galaxy M33. The observations are centered on the nucleus and on thestar forming region NGC 604. We detect a total of 261 sources in an area of\~0.2 square degree down to a flux limit of 3*10^{-16} erg/s/cm^2 whichcorresponds to a luminosity of ~2*10^34 erg/s at a distance of 840 kpc. Fromthe source list we construct the luminosity functions of sources observed inM33. Taking into account background contamination the luminosity functions areconsistent with those of other star forming galaxies. In addition, thecombination of X-ray color analysis and the existence of ``blue'' opticalcounterparts strongly indicate that the X-ray point source population in M33consists of young objects. Above 3*10^35 erg/s there are few X-ray sources inthe locus of the X-ray hardness ratio diagram that is generally populated byLMXBs.Comment: 51 pages, accepted for ApJS, accepted versio