Constraining the Relativistic Thermal and Bulk Kinematic Sunyaev--Zel'dovich Effects

Abstract

When Cosmic Microwave Background (CMB) photons interact with free electrons in the hot gas of galaxy clusters they gain energy via inverse Compton scattering, resulting in a spectral distortion of the CMB called the Sunyaev–Zel’dovich (SZ) effect. This phenomena is invaluable to cosmology as it facilitates measurements of various properties of galaxy clusters and cosmological parameters. In this work, we use CMB maps from the Atacama Cosmology Telescope (ACT) and the Planck satellite as well as the redMaPPer galaxy cluster catalog to fit for the thermal SZ (tSZ effect), the kinetic SZ (kSZ effect), the dust, and the relativistic thermal SZ (rSZ) effect. Though we do not detect kSZ or rSZ at 3σ using an MCMC fitting algorithm, we are able to put constraints on both of these quantities.