ASCA compilation of X-ray properties of hot gas in elliptical galaxies and galaxy clusters: Two breaks in the temperature dependences

Utilizing ASCA archival data of about 300 objects of elliptical galaxies, groups, and clusters of galaxies we performed systematic measurements of the X-ray properties of hot gas in their systems, and compiled them in this paper. The steepness of the luminosity-temperature (LT) relation, L-X proportional to (kT)(alpha), in the range of kT similar to 1.5-15 Kev is alpha = 3.17 +/- 0.15, consistent with previous measurements. In the relation, we find two breaks at around ICM temperatures of 1 keV and 4 keV: alpha = 2.34 +/- 0.29 above 4 keV 3.74 +/- 0.32 in 1.5-5 keV, and 4.03 +/- 1.07 below 1.5 keV. Such two breaks are also evident in the temperature and size relation. The steepness in the LT relation at kT > 4keV is consistent with the scale-relation derived from the CDM model, indicating that the gravitational effect is dominant in richer Clusters, while poorer clusters suffer non-gravity effects. The steep LT relation below I keV is almost attributed to X-ray faint systems of elliptical galaxies and galaxy groups. We found that the ICM mass within the scaling radius R-1500 follows the relation of Al-gas proportional to T2.33+/-0.07 from X-ray faint galaxies to rich clusters. Therefore, we speculate that even such X-ray faint systems contain a lame-scale hot gas, which is too faint to detect.