The eROSITA Final Equatorial-Depth Survey (eFEDS): Presenting The
  Demographics of X-ray Emission From Normal Galaxies
  The $\it{eROSITA}$ Final Equatorial Depth Survey (eFEDS), completed during
the calibration and performance verification phase of the $\it{eROSITA}$
instrument on $\it{Spectrum\, Roentgen\, Gamma}$, delivers data at and beyond
the final depth of the four-year $\it{eROSITA}$ all-sky survey (eRASS:8),
$f_{0.5-2\,\text{ keV}}$ = $1.1\times10^{-14}$ erg s$^{-1}$ cm$^{2}$, over 140
deg$^{2}$. It provides the first view of normal galaxy X-ray emission from
X-ray binaries (XRBs) and the hot interstellar medium at the full depth of
eRASS:8. We use the Heraklion Extragalactic Catalogue (HECATE) of galaxies to
correlate with eFEDS X-ray sources and identify 94 X-ray detected normal
galaxies. We classify galaxies as star-forming, early-type, composite, and AGN
using SDSS and 6dF optical spectroscopy. The eFEDS field harbours 37 normal
galaxies: 36 late-type (star-forming) galaxies and 1 early-type galaxy. There
are 1.9 times as many normal galaxies as predicted by scaling relations via
SIXTE simulations, with an overabundance of late-type galaxies and a dearth of
early-type galaxies. Dwarf galaxies with high specific star formation rate
(SFR) have elevated L$_{\text{X}}$/SFR when compared with specific SFR and
metallicity, indicating an increase in XRB emission due to low-metallicity. We
expect that eRASS:8 will detect 12,500 normal galaxies, the majority of which
will be star-forming, with the caveat that there are unclassified sources in
eFEDS and galaxy catalogue incompleteness issues that could increase the actual
number of detected galaxies over these current estimates. eFEDS observations
detected a rare population of galaxies -- the metal-poor dwarf starbursts --
that do not follow known scaling relations. eRASS is expected to discover
significant numbers of these high-redshift analogues, which are important for
studying the heating of the intergalactic medium at high-redshift.
