The cluster m-t relation from temperature profiles observed with ASCA and ROSAT.
NEVALAINEN J., MARKEVITCH M. and FORMAN W.
Abstract (from CDS):
We calibrate the galaxy cluster mass-temperature (M-T) relation using the temperature profiles of intracluster gas observed with ASCA (for hot clusters) and ROSAT (for cool groups). Our sample consists of apparently relaxed clusters for which the total masses are derived, assuming hydrostatic equilibrium. The sample provides data on cluster X-ray emission-weighted cooling-flow-corrected temperatures and total masses up to r1000. The resulting M-T scaling in the 1-10 keV temperature range is M1000=1.23±0.20x1015 h–150 M☉<T>z=0/10 keV1.79±0.14 with 90% confidence errors, or significantly (99.99% confidence) steeper than the self-similar relation M∝T3/2. For any given temperature, our measured mass values are significantly smaller compared to the simulation results of Evrard, Metzler, & Navarro that are frequently used for mass-temperature scaling. The higher temperature subsample (kT≥4 keV) is consistent with M∝T3/2, allowing the possibility that the self-similar scaling breaks down at low temperatures, perhaps due to heating by supernovae that is more important for low-temperature groups and galaxies, as suggested by earlier works.
Cosmology: Observations - Cosmology: Dark Matter - Galaxies: Clusters: General - Galaxies: Intergalactic Medium - X-Rays: Galaxies