paper

Is the non-isothermal double -model incompatible with no time evolution of galaxy cluster gas mass fraction ?

arXiv:1711.05173 · doi:10.1016/j.astropartphys.2018.02.001

Abstract

In this paper, we propose a new method to obtain the depletion factor , the ratio by which the measured baryon fraction in galaxy clusters is depleted with respect to the universal mean. We use exclusively galaxy cluster data, namely, X-ray gas mass fraction () and angular diameter distance measurements from Sunyaev-Zel'dovich effect plus X-ray observations. The galaxy clusters are the same in both data set and the non-isothermal spherical double -model was used to describe their electron density and temperature profiles. In order to compare our results with those from recent cosmological hydrodynamical simulations, we suppose a possible time evolution for , such as, . As main conclusions we found that: the value is in full agreement with the simulations. { On the other hand, although the value found in our analysis is compatible with within 2 c.l., our results show a non-negligible time evolution for the depletion factor, unlike the results of the simulations. However, we also put constraints on by using the measurements and angular diameter distances obtained from the flat CDM model (Planck results) and from a sample of galaxy clusters described by a elliptical profile. For these cases no significant time evolution for was found. Then, if a constant depletion factor is an inherent characteristic of these structures, our results show that the spherical double -model used to describe the galaxy clusters considered does not affect the quality of their measurements.

10 pages, 4 figures, I table, Accepted for publication in the Astroparticle Physics

References in corpus (6)

Cited by in corpus (6)