The 6.7-keV iron-line emission in the Galactic Centre

We use recent XMM-Newton observations to study the ''diffuse'' X-ray emission seen in the Galactic Centre Region. Spectrally, the emission can be separated into three major components, each characterised by a prominent spectral line. Using these lines as tracers, we investigate the underlying spatial distribution of the various components. Specifbally, we find the 6.7-keV line of helium-like iron, has a relatively smooth, circularly symmetric distribution centred on Sgr A* and a surface brightness which falls off with radius as r−0.87±0.06 over the range r = 3' − 12'. This mirrors the distribution of the underlying stellar population and adds strong support to the hypothesis that the 6.7-keV line and the associated hard thermal continuum (with kT ≈ 8 keV) originates in the summed emission of faint point sources.