F. Akimoto1,2, A. Furuzawa1, K. Yamashita1 and Y. Tawara1

1: Department of Physics, Nagoya University
2: Research Center for Advanced Energy Conversion, Nagoya University

Abstract

150 clusters of galaxies observed with ASCA (including group of galaxies 20%, binary galaxies a few %, galaxy 10%) are analyzed, using common manner to minimize systematic deviation due to instrumental characteristics. Obtained correlation between X-ray luminosity and gas temperature (LX-kT relation) from galaxies to rich clusters enables us to discuss formation and evolution of a gravitationally bounded system above 1012Mo. We found that the slope of this relation was changed at a gas temperature of 3keV. Below 3keV, the slope of LX-kT relation is much steeper than that above 3keV. It can be described that a small system is much affected by preheating or a gas fraction in a small system is smaller than that in a large system unrelated to the preheating. However, obtained correlation between entropy and temperature shows no sign of the preheating. On the other hand, as the size of system becomes to be smaller, the central gas density is higher and gas fraction is smaller. This means the concentration of the gas is smaller than that of dark matter in a small system. We will discuss the origin of the discontinuity of LX-kT relation with other correlations among the available parameters. upercluster with the temperature map, galaxy density, velocity map.