Chemical enrichment of the ICM within the Virgo cluster I: radial profiles

TL;DR

This study analyzes the distribution of elemental abundances in the Virgo cluster's intracluster medium using XMM-Newton data, revealing temperature discontinuities and supporting early metal enrichment.

Contribution

It provides detailed radial profiles of multiple elemental abundances and introduces a new calibration method for velocity measurements in the ICM.

Findings

Temperature discontinuities at ~30 kpc and ~90 kpc correspond to cold fronts.

The ICM shows a flat SNIa ratio profile, indicating early enrichment.

Cooler gas regions are more metal-rich.

Abstract

We present a detailed analysis of the elemental abundances distribution of the Virgo cluster using {\it XMM-Newton} observations. We included in the analysis a new EPIC-pn energy scale calibration which allow us to measure velocities with uncertainties down to $\Delta v \sim 150$ km/s. We investigate the radial distribution of O, Ne, Mg, Si, Ar, S, Ca, Ni and Fe. We found that the best-fit model is close to a single-temperature component for distances $>80$~kpc and the cooler gas is more metal-rich. Discontinuities in temperature are found around $\sim30$~kpc and $\sim90$~kpc, which correspond to the radius of the cold fronts. We modeled elemental X/Fe ratio profiles with a linear combination of SNIa and SNcc models. We found a flat radial distribution of SNIa ratio over the total cluster enrichment, which supports an early ICM enrichment scenario, with most of the metals present being produced prior to clustering.