Constraints on the CMB Temperature Evolution using Multi-Band Measurements of the Sunyaev Zel'dovich Effect with the South Pole Telescope

Understand

The adiabatic evolution of the temperature of the cosmic microwave background (CMB) is a key prediction of standard cosmology.

• We study deviations from the expected adiabatic evolution of the CMB temperature of the form $T(z) =T_0(1+z)^{1-\alpha}$ using measurements of the spectrum of the Sunyaev Zel'dovich Effect with the South Pole Telescope (SPT).
• We present a method for using the ratio of the Sunyaev Zel'dovich signal measured at 95 and 150 GHz in the SPT data to constrain the temperature of the CMB.
• We demonstrate that this approach provides unbiased results using mock observations of clusters from a new set of hydrodynamical simulations.