Debiased Galaxy Cluster Pressure Profiles from X-ray Observations and Simulations

Yizhou He; Philip Mansfield; Markus M. Rau; Hy Trac; Nicholas Battaglia

doi:10.3847/1538-4357/abd0ff

paper

Debiased Galaxy Cluster Pressure Profiles from X-ray Observations and Simulations

arXiv:2008.04334 · doi:10.3847/1538-4357/abd0ff

Abstract

We present an updated model for the average cluster pressure profile, adjusted for hydrostatic mass bias by combining results from X-ray observations with cosmological simulations. Our model estimates this bias by fitting a power-law to the relation between the "true" halo mass and X-ray cluster mass in hydrodynamic simulations (IllustrisTNG, BAHAMAS, and MACSIS). As an example application, we consider the REXCESS X-ray cluster sample and the Universal Pressure Profile (UPP) derived from scaled and stacked pressure profiles. We find adjusted masses, $M_{500c},$ that are $≲$ 15% higher and scaled pressures $P / P_{500c}$ that have $≲$ 35% lower normalization than previously inferred. Our Debiased Pressure Profile (DPP) is well-fit by a Generalized Navarro-Frenk-White (GNFW) function, with parameters $[P_{0}, c_{500}, α, β, γ] = [5.048, 1.217, 1.192, 5.490, 0.433]$ and does not require a mass-dependent correction term. When the DPP is used to model the Sunyaev-Zel'dovich (SZ) effect, we find that the integrated Compton $Y - M$ relation has only minor deviations from self-similar scaling. The thermal SZ angular power spectrum is lower in amplitude by approximately 30%, assuming nominal cosmological parameters (e.g. $Ω_{m} = 0.3$ , $σ_{8} = 0.8$ ), and is broadly consistent with recent Planck results without requiring additional bias corrections.

arXiv comment13 pages, 5 figures, 3 tables

Debiased Galaxy Cluster Pressure Profiles from X-ray Observations and Simulations

Abstract

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