High‐Resolution X‐Ray Spectroscopic Constraints on Cooling‐Flow Models for Clusters of Galaxies

Abstract

We present high-resolution X-ray spectra of 14 putative cooling-flow clusters of galaxies obtained with the Reflection Grating Spectrometer on XMM-Newton. The clusters in the sample span a large range of temperatures and mass deposition rates. Various of these spectra exhibit line emission from O VIII, Ne X, Mg XII and XI, Al XIII and XII, Si XIV and XIII, N VII, and C VI as well as all Fe L ions. The spectra exhibit strong emission from cool plasma at just below the ambient temperature, T 0 , down to T 0 /2, but also exhibit a severe deficit of emission relative to the predictions of the isobaric cooling-flow model at lower temperatures (