33 research outputs found
Diffuse Thermal X-Ray Emission in the Core of the Young Massive Cluster Westerlund 1
We present an analysis of the diffuse hard X-ray emission in the core of the
young massive Galactic cluster Westerlund 1 based on a 48 ks XMM-Newton
observation. Chandra results for the diffuse X-ray emission have indicated a
soft thermal component together with a hard component that could be either
thermal or non-thermal. We seek to resolve this ambiguity regarding the hard
component exploiting the higher sensitivity of XMM-Newton to diffuse emission.
Our new X-ray spectra from the central (2' radius) diffuse emission are found
to exhibit He-like Fe 6.7 keV line emission, demonstrating that the hard
emission in the cluster core is predominantly thermal in origin. Potential
sources of this hard component are reviewed, namely an unresolved Pre-Main
Sequence population, a thermalized cluster wind and Supernova Remnants
interacting with stellar winds. We find that the thermalized cluster wind
likely contributes the majority of the hard emission with some contribution
from the Pre-Main Sequence population. It is unlikely that Supernova Remnants
are contributing significantly to the Wd1 diffuse emission at the current
epoch
The distribution of X-ray sources in the Milky Way
Wetensch. publicati
A 1415 MHz survey of Seyfert and related galaxies. III
Wetensch. publicatieFaculteit der Wiskunde en Natuurwetenschappe
Accurate optical positions of Seyfert galaxies
Wetensch. publicatieFaculteit der Wiskunde en Natuurwetenschappe