Extended Source Analysis for Grating Spectrometers

Dispersive spectrometers such as the XMM-Newton RGS and the Chandra HETGS/LETGS are nominally designed and used to study “point sources”, that is sources unresolved by the telescope system. When used to observe “extended sources” the resolving power of these spectrometers is generally degraded; however, useful highresolution information may still be extracted using non-standard analysis techniques. Which technique to use and the amount of information extractable from an observation depend on the spatial and spectral properties of the object. Examples are given of “spatial-spectral” techniques that are in development, in particular ones being used to extract high-resolution results from Chandra HETGS observations of the supernova remnants E0102, N132D, N103B, and Cas A.