Impact of Cluster Physics on the Sunyaev-Zel'dovich Power Spectrum

Understand

We use an analytic model to investigate the theoretical uncertainty on the thermal Sunyaev-Zel'dovich (SZ) power spectrum due to astrophysical uncertainties in the thermal structure of the intracluster medium.

• Our model accounts for star formation and energy feedback (from supernovae and active galactic nuclei) as well as radially dependent non-thermal pressure support due to random gas motions, the latter calibrated by recent hydrodynamical simulations.
• We compare the model against X-ray observations of low redshift clusters, finding excellent agreement with observed pressure profiles.
• Varying the levels of feedback and non-thermal pressure support can significantly change both the amplitude and shape of the thermal SZ power spectrum.