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A recent stacking analysis of Planck HFI data of galaxy clusters (Hurier 2016) allowed to derive the cluster temperatures by using the relativistic corrections to the Sunyaev-Zeldovich effect (SZE). However, the temperatures of high-temperature clusters, as derived from this analysis, resulted to be basically higher than the temperatures derived from X-ray measurements, at a moderate statistical significance of $1.5sigma$. This discrepancy has been attributed by Hurier (2016) to calibration issues. In this paper we discuss an alternative explanation for this discrepancy in terms of a non-thermal SZE astrophysical component. We find that this explanation can work if non-thermal electrons in galaxy clusters have a low value of their minimum momentum ($p_1sim0.5-1$), and if their pressure is of the order of $20-30%$ of the thermal gas pressure. Both these conditions are hard to obtain if the non-thermal electrons are mixed with the hot gas in the intra cluster medium, but can be possibly obtained if the non-thermal electrons are mainly confined in bubbles with high content of non-thermal plasma and low content of thermal plasma, or in giant radio lobes/relics located in the outskirts of clusters. In order to derive more precise results on the properties of non-thermal electrons in clusters, and in view of more solid detections of a discrepancy between X-rays and SZE derived clusters temperatures that cannot be explained in other ways, it would be necessary to reproduce the full analysis done by Hurier (2016) by adding systematically the non-thermal component of the SZE.
We report the direct detection of the kinetic Sunyaev-Zeldovich (kSZ) effect in galaxy clusters with a 3.5 sigma significance level. The measurement was performed by stacking the Planck map at 217 GHz at the positions of galaxy clusters from the Wen-
We introduce the Marenostrum-MultiDark SImulations of galaxy Clusters (MUSIC) Dataset, one of the largest sample of hydrodynamically simulated galaxy clusters with more than 500 clusters and 2000 groups. The objects have been selected from two large
In this work we calculate the Sunyaev-Zeldovich (SZ) effect due to the $e^+e^-$ from dark matter (DM) annihilation in galaxy clusters. Two candidates of DM particle, (1) the weakly-interacting massive particle (WIMP) and (2) the light dark matter (LD
[Abridged] Inverse Compton scattering of CMB fluctuations off cosmic electron plasma generates a polarization of the associated Sunyaev-Zeldovich (SZ) effect. This signal has been studied so far mostly in the non-relativistic regime and for a thermal
Starting from a covariant formalism of the Sunyaev-Zeldovich effect for the thermal and non-thermal distributions, we derive the frequency redistribution function identical to Wrights method assuming the smallness of the photon energy (in the Thomson