**Constraining the evolution of the CMB temperature with SZ measurements from Planck data**

*G. Luzzi, R. T. Génova-Santos, *__C. J. A. P. Martins__, M. de Petris, L Lamagna

**Abstract**

The CMB temperature-redshift relation, *T*_{CMB}(*z*)=*T*_{0}(1+*z*), is a key prediction of the standard cosmology but is violated in many non-standard models. Constraining possible deviations from this law is an effective way to test the ΛCDM paradigm and to search for hints of new physics. We have determined *T*_{CMB}(*z*), with a precision up to 3%, for a subsample (103 clusters) of the Planck SZ cluster catalog, at redshifts in the range 0.01–0.94, using measurements of the spectrum of the Sunyaev-Zel'dovich (SZ) effect obtained from *Planck* temperature maps at frequencies from 70 to 353 GHz. The method adopted to provide individual determinations of *T*_{CMB}(*z*) at cluster redshift relies on the use of SZ intensity change, Δ *I*_{SZ}(ν) at different frequencies and on a Monte Carlo Markov chain approach. By applying this method to the sample of 103 clusters, we limit possible deviations of the form *T*_{CMB}(*z*)=*T*_{0}(1+*z*)^{1−β} to be β= 0.012 ± 0.016, at 1σ uncertainty, consistent with the prediction of the standard model. Combining these measurements with previously published results, we get β=0.013±0.011.

**Journal of Cosmology and Astroparticle Physics**

Volume 09, Page 011

September 2015

**DOI:** 10.1088/1475-7516/2015/09/011

**ADS Bibliographic code:** 2015JCAP...09..011L