X-ray Imaging Spectroscopy of Abell 1835

Abstract

We present detailed spatially-resolved spectroscopy results of the observation of Abell 1835 using the European Photon Imaging Cameras (EPIC) and the Reflection Grating Spectrometers (RGS) on the XMM-Newton observatory. Abell 1835 is a luminous (\(10^{46}\) ergs \({s}^{-1}\)), medium redshift (\(z=0.2523\)), X-ray emitting cluster of galaxies. The observations support the interpretation that large amounts of cool gas are present in a multi-phase medium surrounded by a hot (\(kT_{e}\)=8.2 keV) outer envelope. We detect O VIII Ly\(\alpha\) and two Fe XXIV complexes in the RGS spectrum. The emission measure of the cool gas below \(kT_{e}\)=2.7 keV is much lower than expected from standard cooling-flow models, suggesting either a more complicated cooling process than simple isobaric radiative cooling or differential cold absorption of the cooler gas.