Thermodynamic perturbations in the X-ray halo of 33 clusters of galaxies
  observed with Chandra ACIS
  In high-resolution X-ray observations of the hot plasma in clusters of
galaxies significant structures caused by AGN feedback, mergers, and turbulence
can be detected. Many clusters have been observed by Chandra in great depth and
at high resolution. Using archival data taken with the Chandra ACIS instrument
the aim was to study thermodynamic perturbations of the X-ray emitting plasma
and to apply this to better understand the thermodynamic and dynamic state of
the intra cluster medium (ICM). We analysed deep observations for a sample of
33 clusters with more than 100 ks of Chandra exposure each at distances between
redshift 0.025 and 0.45. The combined exposure of the sample is 8 Ms. Fitting
emission models to different regions of the extended X-ray emission we searched
for perturbations in density, temperature, pressure, and entropy of the hot
plasma. For individual clusters we mapped the thermodynamic properties of the
ICM and measured their spread in circular concentric annuli. Comparing the
spread of different gas quantities to high-resolution 3D hydrodynamic
simulations, we constrain the average Mach number regime of the sample to
Mach1D ~ 0.16 +- 0.07. In addition we found a tight correlation between
metallicity, temperature and redshift with an average metallicity of Z ~ 0.3 +-
0.1 Z(solar). This study provides detailed perturbation measurements for a
large sample of clusters which can be used to study turbulence and make
predictions for future X-ray observatories like eROSITA, Astro-H, and Athena.
