X-ray Signatures of Non-equilibrium Ionization Effects in Galaxy Cluster Accretion Shock Regions

  title={X-ray Signatures of Non-equilibrium Ionization Effects in Galaxy Cluster Accretion Shock Regions},
  author={Ka-wah Wong and Craig L. Sarazin and L. Verdes-Montenegro University of Alabama and Tuscaloosa and University of Virginia and Mit Kavli Institute for Astrophysics and Space Research},
  journal={The Astrophysical Journal},
The densities in the outer regions of clusters of galaxies are very low, and the collisional timescales are very long. As a result, heavy elements will be under-ionized after they have passed through the accretion shock. We have studied systematically the effects of non-equilibrium ionization for relaxed clusters in the ΛCDM cosmology using one-dimensional hydrodynamic simulations. We found that non-equilibrium ionization effects do not depend on cluster mass, but depend strongly on redshift… Expand
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