Self-similarity of clusters of galaxies and the 
relation
CEA/Saclay DSM/DAPNIA/ Service d'Astrophysique, L'Orme des Merisiers, Bât. 709, 91191 Gif-sur-Yvette, France e-mail: marnaud@discovery.saclay.cea.fr
Corresponding author: D. M. Neumann, ddon@cea.fr
Received:
27
April
2001
Accepted:
28
May
2001
In this paper based on ROSAT/PSPC data we investigate the emission
measure profiles of a sample of hot clusters of galaxies (
keV) in
order to explain the differences between observed and theoretically predicted
LX-T relation. Looking at the form of the emission measure profiles as well as
their normalizations we find clear indication that indeed the profiles
have similar shapes once scaled to the virial radius, however, the
normalization of the profiles shows a strong temperature dependence. We
introduce a Mgas-T relation with the dependence 
. This relationship explains the observed LX-T relation
and reduces the scatter in the scaled
profiles by a factor of 2 when compared to the classical scaling. We
interpret this finding as strong indication that the Mgas-T relation in
clusters deviates from classical scaling.
Key words: galaxies: clusters: general / cosmology: observations, dark matter / X-rays: general
© ESO, 2001