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

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 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 function, with parameters [P₀, c₅₀₀, 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, σ₈ = 0.8), and is broadly consistent with recent Planck results without requiring additional bias corrections.