Advances in Astronomy and Space Physics, Volume 9, Issue 1-2, PP. 8-13 (2019)
doi: 10.17721/2227-1481.9.8-13

X-ray scaling relations of elliptical galaxies

Iu. V. Babyk

Main Astronomical Observatory of the NAS of Ukraine, 27 Akademica Zabolotnoho Str., 03143, Kyiv, Ukraine
Department of Physics and Astronomy, University of Waterloo, 200 University Avenue West, Waterloo, ON N2L 5G1, Canada
Waterloo Institute for Astrophysics, University of Waterloo, 200 University Avenue West, Waterloo, ON N2L 5G1, Canada

We present the X-ray scaling relations of a sample of elliptical galaxies using X-ray Chandra observations. We use a single β-model to reconstruct the density gas profile and the hydrostatic equation to measure the total mass. We build X-ray scaling relations between temperature, luminosity and total mass at 5Re. Our sample in- cludes gas-poor objects that help us to extend already published LX − T , M − T and LX − M scaling relations to lower magnitudes. The derived slopes for all three relations are much steeper than those for galaxy clusters and groups, and are extreme compared to self-similar models considering gravity only. This increase of steepness from clusters to galaxies indicates that non-thermal processes (e.g. AGN feedback) have a stronger influence on the small-scale systems. Our results indicate that the hot interstellar medium of gas-poor early-type galaxies is not in the wind/outflow state as suggested by recent hydrodynamical simulations. We also discuss the possible biases of our calculations and compare our results to recent papers.

galaxies: elliptical and lenticular, cD; galaxies: evolution; galaxies: formation