Chemical Evolution in Sersic 159-03 Observed with Xmm-Newton

de Plaa, Jelle ; Werner, N. ; Bykov, A.M. ; Kaastra, J.S. ; Mendez, M. ; Vink, J. ; Bleeker, J.A.M. ; Bonamente, M. ; Peterson, J.R. ; /SRON, Utrecht /Utrecht, Astron. Inst. /Ioffe Phys. Tech. Inst. /Alabama U., Huntsville /KIPAC, Menlo Park

Stanford Linear Accelerator Center

关键词: Abundance;    Spectra;    71 Classical And Quantum Mechanics, General Physics;    Oxygen;    Iron;   

DOI  :  10.2172/877208
RP-ID  :  SLAC-PUB-11739
RP-ID  :  AC02-76SF00515
RP-ID  :  877208

美国|英语

来源: UNT Digital Library

【 摘 要 】

Using a new long X-ray observation of the cluster of galaxies Sersic 159-03 with XMM-Newton, we derive radial temperature and abundance profiles using single- and multi-temperature models. The fits to the EPIC and RGS spectra prefer multi-temperature models especially in the core. The radial profiles of oxygen and iron measured with EPIC/RGS and the line profiles in RGS suggest that there is a dip in the O/Fe ratio in the centre of the cluster compared to its immediate surroundings. A possible explanation for the large scale metallicity distribution is that SNIa and SNII products are released in the ICM through ram-pressure stripping of in-falling galaxies. This causes a peaked metallicity distribution. In addition, SNIa in the central cD galaxy enrich mainly the centre of the cluster with iron. This excess of SNIa products is consistent with the low O/Fe ratio we detect in the centre of the cluster. We fit the abundances we obtain with yields from SNIa, SNII and Population-III stars to derive the clusters chemical evolution. We find that the measured abundance pattern does not require a Population-III star contribution. The relative contribution of the number of SNIa with respect to the total number of SNe which enrich the ICM is about 25-50%. Furthermore, we discuss the possible presence of a non-thermal component in the EPIC spectra. A potential source of this non-thermal emission can be inverse-Compton scattering between Cosmic Microwave Background (CMB) photons and relativistic electrons, which are accelerated in bow shocks associated with ram-pressure stripping of in-falling galaxies.