SZ/X-ray scaling relations using X-ray data and Planck Nominal maps

TL;DR

This study examines the SZ/X-ray scaling relations in galaxy clusters using ROSAT and Planck data, confirming models and revealing a low-mass discrepancy in the $L_X-M$ relation.

Contribution

It extends previous analyses by including a larger, lower-mass, and lower-redshift cluster sample, testing the $eta=2/3$ model and pressure profiles against Planck measurements.

Findings

The $eta=2/3$ model agrees with Planck measurements within the X-ray emitting region.

The universal pressure profile overestimates the signal by 15-21%.

The $L_X-M$ relation shows a break at low masses, indicating a deviation from self-similar evolution.

Abstract

We determine the relation between the Comptonization parameter predicted using X-ray data $Y_{C,Xray}$ and the X-ray luminosity $L_X$, both magnitudes derived from ROSAT data, with the Comptonization parameter $Y_{C,SZ}$ measured on {\it Planck} 2013 foreground cleaned Nominal maps. The 560 clusters of our sample includes clusters with masses $M\ge 10^{13}M_\odot$, one order of magnitude smaller than those used by the Planck Collaboration in a similar analysis. It also contains eight times more clusters in the redshift interval $z\le 0.3$. The prediction of the $\beta=2/3$ model convolved with the Planck antenna beam agrees with the anisotropies measured in foreground cleaned Planck Nominal maps within the X-ray emitting region, confirming the results of an earlier analysis (Atrio-Barandela et al. 2008). The universal pressure profile overestimates the signal by a 15-21\% depending on the angular aperture. We show that the discrepancy is not due to the presence of {\it cool-core} systems but it is an indication of a brake in the $L_X-M$ relation towards low mass systems. We show that relation of the Comptonization parameter averaged over the region that emits 99\% of the X-ray flux and and the X-ray luminosity is consistent with the predictions of the self-similar model. We confirm previous findings that the scaling relations studied here do not evolve with redshift within the range probed by our catalog.