Constraining the redshift evolution of the Cosmic Microwave Background black-body temperature with PLANCK data

TL;DR

This study uses Planck satellite data and galaxy clusters to precisely test the evolution of the CMB temperature with redshift, confirming the standard cosmological model's predictions.

Contribution

It provides the most accurate constraint to date on the CMB temperature-redshift relation using only CMB data, with a novel analysis method that minimizes bias.

Findings

Measured deviation parameter α = -0.007 ± 0.013, consistent with standard model.

Quantified potential bias in the measurement as |δα| ≤ 0.02.

Confirmed the adiabatic evolution of the Universe's CMB temperature with high precision.

Abstract

We constrain the deviation of adiabatic evolution of the Universe using the data on the Cosmic Microwave Background (CMB) temperature anisotropies measured by the {\it Planck} satellite and a sample of 481 X-ray selected clusters with spectroscopically measured redshifts. To avoid antenna beam effects, we bring all the maps to the same resolution. We use a CMB template to subtract the cosmological signal while preserving the Thermal Sunyaev-Zeldovich (TSZ) anisotropies; next, we remove galactic foreground emissions around each cluster and we mask out all known point sources. If the CMB black-body temperature scales with redshift as $T(z)=T_0(1+z)^{1-\alpha}$, we constrain deviations of adiabatic evolution to be $\alpha=-0.007\pm 0.013$, consistent with the temperature-redshift relation of the standard cosmological model. This result could suffer from a potential bias $\delta\alpha$ associated with the CMB template, that we quantify it to be $|\delta\alpha|\le 0.02$ and with the same sign than the measured value of $\alpha$, but is free from those biases associated with using TSZ selected clusters; it represents the best constraint to date of the temperature-redshift relation of the Big-Bang model using only CMB data, confirming previous results.