X-ray measurement of the elemental abundances at the outskirts of the Perseus cluster with Suzaku

TL;DR

This study measures metal abundances in the outskirts of the Perseus cluster using Suzaku X-ray data, revealing uniform Fe and high Mg levels with a significant Mg/Fe ratio increase compared to the center.

Contribution

First detailed measurement of Mg and Fe abundances in the Perseus cluster outskirts using Suzaku, highlighting elemental distribution and ratios.

Findings

Fe abundance is ~0.3 solar at outskirts

Mg abundance is ~1 solar at outskirts

Mg/Fe ratio is about 4 times higher in outskirts than in the center

Abstract

We report on the abundance of metals (Mg and Fe) in the intracluster medium (ICM) at the outskirts (0.2 r200 - 0.8 r200) of the Perseus cluster. The X-ray spectra were obtained in the Suzaku/XIS mapping observations of this region. We employ single temperature models to fit all the X-ray spectra. The ICM temperature smoothly decreases toward the outer region from 6 keV to 4 keV. The Fe abundance is uniformly distributed at the outskirts (~0.3 solar). The Mg abundance is ~1 solar at the outskirts. The solar ratios of Mg/Fe of the outskirts region (Mg/Fe ~4) are a factor of 4 larger than those of the central region. Various systematic effects, including the spatial fluctuations in the cosmic X-ray background, are taken into account and evaluated. These our results have not changed significantly.