SRG/eROSITA all-sky survey catalogs (eRASS1)

A smaller catalogue of 5466 sources detected in the less sensitive but harder 2.3-5keV band is the result of the first true imaging survey of the entire sky above 2keV. We present methods to identify and flag potential spurious sources in the catalogues, which we applied for this work, and we tested and validated the astrometric accuracy via cross-comparison with other X-ray and multi-wavelength catalogues. We show that the number counts of X-ray sources in eRASS1 are consistent with those derived over narrower fields by past X-ray surveys of a similar depth, and we explore the number counts variation as a function of the location in the sky.

Adopting a uniform all-sky flux limit (at 50% completeness) of F_0.5-2keV_>5x10^-14^erg/s/cm^2^, we estimate that the eROSITA all-sky survey resolves into individual sources about 20% of the cosmic X-ray background in the 1-2keV range. The catalogues presented here form part of the first data release (DR1) of the SRG/eROSITA all-sky survey. Beyond the X-ray catalogues, DR1 contains all detected and calibrated event files, source products (light curves and spectra), and all-sky maps.

Illustrative examples of these are provided.