Chemical enrichment of ICM within the Centaurus cluster - I. Radial profiles

Abstract

We examine deep XMM-Newton European Photon Imaging Camera pn observations of the Centaurus cluster to study the hot intracluster medium (ICM) and radial metal distributions within such an environment. We found that the best-fitting spectral model corresponds to a lognormal temperature distribution, with discontinuities around ∼10, ∼50, and ∼100 kpc, also observed in the abundance distributions. We measured the radial profiles of O, Si, S, Ar, Ca, and Fe. These profiles reveal prominent negative gradients for distances <90 kpc, which then transition to flatter profiles. We modelled X/Fe ratio profiles with a linear combination of core-collapse supernova and Type Ia supernova (SNIa) models. The best-fitting model suggests a uniform SNIa percentage contribution to the total cluster enrichment, thus supporting an early enrichment of the ICM, with most of the metals present being produced before clustering.