XMM-Newton observation of the Tycho supernova remnant

We present the observation of the Tycho supernova remnant obtained with the EPIC and RGS instruments onboard the XMM-Newton satellite. We compare imag es and azimuthally averaged radial profiles in emission lines from differen t elements (silicon and iron) and different transition lines of iron (Fe L and Fe It). While the Fe XVII L line and Si XIII K line images are globally spatially coincident, the Fe Ii emission clearly peaks at a smaller radius , indicating a higher temperature toward the reverse shock. This is qualita tively the profile expected when the reverse shock, after travelling throug h the outer power-law density profile, has entered the central plateau of t he ejecta. The high energy continuum map has an overall smooth distribution , with a similar extent to the radio emission. Its radial profile peaks fur ther out than the lines emission. Brighter and harder continuum regions are observed with a rough bipolar symmetry in the eastern and western edges. T he spectral analysis of the southeastern knots supports spatial variations of the relative abundance of silicon and iron, which implies an incomplete mixing of the silicon and iron layers.