Relations of X-ray properties of 150 galaxy clusters observed with ASCA
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.