XMM-Newton observations of Sagittarius A East

We present an analysis of a recent XMM-Newton observation of Sgr A East, a supernova remnant located close to the Galactic Centre. Very high-quality X-ray spectra reveal many emission lines from highly ionized atoms consistent with a multitemperature thin thermal plasma in ionization equilibrium. We use a two-temperature model to fit the spectra and derive temperatures of 1 and 4 keV. There is significant concentration of iron (Fe) towards the centre of the X-ray source such that the Fe abundance varies from similar to4 times solar in the core down to similar to0.5 solar in the outer regions, which contrasts with the rather uniform distribution of other metals such as sulphur (S), argon (Ar) and calcium (Ca), which have abundances in the range 1-3. The derived total energy, mass and abundance pattern are consistent with a single supernova event, of either Type Ia or Type II origin, involving a relatively low-mass progenitor star. A weak 6.4-keV neutral Fe fluorescence line is also detected, the illumination source most likely being Sgr A East itself. The morphology and spectral characteristics of Sgr A East show no clear linkage to putative past activity in Sgr A.