X-ray Temperature and Mass Measurements to the Virial Radius of Abell 1413 with Suzaku

TL;DR

This study uses Suzaku X-ray observations to measure the temperature and mass profile of galaxy cluster Abell 1413 out to its virial radius, revealing a temperature drop and flatter entropy profile consistent with other clusters.

Contribution

First measurement of Abell 1413's outskirts with Suzaku, extending previous data and analyzing systematic errors for accurate temperature and mass profiles.

Findings

Temperature drops to about 3 keV at the virial radius.

Entropy profile flattens beyond 0.5 r200, similar to other clusters.

Cluster mass at virial radius is approximately 7.5×10^14 solar masses.

Abstract

We present X-ray observations of the northern outskirts of the relaxed galaxy cluster A1413 with Suzaku, whose XIS instrument has the low intrinsic background needed to make measurements of these low surface brightness regions. We excise 15 point sources superimposed on the image above a flux of $1\times 10^{-14}$ \fluxunit (2--10keV) using XMM-Newton and Suzaku images of the cluster. We quantify all known systematic errors as part of our analysis, and show our statistical errors encompasses them for the most part. Our results extend previous measurements with Chandra and XMM-Newton, and show a significant temperature drop to about 3keV at the virial radius, $r_{200}$. Our entropy profile in the outer region ($> 0.5 r_{200}$) joins smoothly onto that of XMM-Newton, and shows a flatter slope compared with simple models, similar to a few other clusters observed at the virial radius. The integrated mass of the cluster at the virial radius is approximately $7.5\times10^{14}M_{\odot}$ and varies by about 30% depending on the particular method used to measure it.