Study the hot extended X-ray emission around z<0.1 galaxies with eRASS1 data
Yi Zhang; Johan Comparat; Andrea Meloni; Gabriele Ponti
Studying the distribution and characteristics of gas around galaxies is important to understand the evolution of central galaxy. The majority of gas is virialized to 10^6 K and produce X-ray emission. This emission has been mainly observed and studied around nearby bright galaxies by Chandra and XMM-Newton, due to its faintness. Another way to increase the statistics is stacking, which needs the large area scan X-ray telescope and the corresponding complete galaxy catalog. Thanks to the eROSITA, we can take advantage of the half sky area and Legacy DR9 catalog to stack and study the hot gas component around galaxies. In this work, we give the X-ray intensity profile around galaxies in mass bins from 1e10 to 5e11 solar mass and the relation between the X-ray luminosity and stellar mass of galaxy. We split the galaxies into blue and red galaxies to explore the difference of the X-ray emission. We analyse the effect of projected background and foreground galaxies and find it contribute a lot to the X-ray emission, especially for lower mass galaxies. We are trying to model this projection effect.