Radial profile and lognormal fluctuations of the intracluster medium as the origin of systematic bias in spectroscopic temperature

  title={Radial profile and lognormal fluctuations of the intracluster medium as the origin of systematic bias in spectroscopic temperature},
  author={Hajime Kawahara and Yasushi Suto and Tetsu Kitayama and Shin-ichi Sasaki and Mamoru Shimizu and Elena Rasia and Klaus Dolag},
  journal={The Astrophysical Journal},
The origin of the recently reported systematic bias in the spectroscopic temperature of galaxy clusters is investigated using a cosmological hydrodynamic simulation. We find that the local inhomogeneities of the gas temperature and density, after being corrected for their global radial profiles, have a nearly universal distribution that resembles a lognormal function. Based on this lognormal approximation for the fluctuations in the intracluster medium, we develop an analytical model that… Expand

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