Presentation #300.03 in the session ISM/Galaxies.
Studying the distribution and properties of hot gas around galaxies (hot CGM) is helpful to understand the galaxy evolution and explain the bi-modality of the galaxy population, but its observation is challenging. The eROSITA X-ray all-sky survey allows us to study the hot CGM with a large sample of galaxies and measure a general relationship between the hot CGM and galaxy properties, i.e. stellar mass. Using the DESI Legacy Imaging Surveys DR9 (LS DR9), we build an isolated galaxy sample containing about 213k galaxies, with z<0.4 and 9.5<logM*<11.5, located in a sparse environment. Using the latest self-calibrated halo-based group finding algorithm applied to the SDSS Main galaxy sample (MGS), we build a central galaxy sample containing about 85k galaxies with z<0.19 and 10<logM*<11.5. By stacking the galaxies, we detect extended hot CGM to the virial radius around MW-like and more massive galaxies. The X-ray surface brightness profile of the hot CGM can be described with the beta model with beta=0.4. The relationship between the X-ray luminosity of hot CGM and the stellar mass of the galaxy is measured down to logM*=9.5, which can be fitted with a linear relation with an index of about 2.0. We also build a galaxy sample binned in the halo mass and measure the relation between the X-ray luminosity of hot CGM and the halo mass down to logMhalo=11.5, which can be fitted with a linear relation with an index of about 1.0. The relationships we measured agree well with previous works that studied the hot CGM above M31-mass. Below M31-mass, our results open the window of new constraints on the galaxy evolution models, i.e. the feedback processes. We split the galaxy samples into star-forming or quiescent subsamples and stacked them separately. The difference in the X-ray luminosity between star-forming or quiescent galaxies is less than 1 σ in the isolated galaxy sample.