X-Ray Proper Motions in Kepler's SNR

We present the first high resolution X-ray proper motion study for Kepler's Supernova Remnant, using data from the Chandra ACIS-S3 detector in 2000 and 2004. Using a spectral analysis, we separate the X-ray emission into components dominated by the outer shock, the clumpy shocked circumstellar material, and the reverse shocked ejecta.

We show the proper motions of these various classes, which will be used to construct an overall dynamical picture of this historical SNR. We investigate the discrepancy, seen at lower resolution, of the x-ray expansion rate being twice that of the radio (Hughes 1999). This work is supported, in part, by the Harvard-Smithsonian Astrophysical Observatory under grant GO4-5075X and by the Space Telescope Science Institute under grant HST-GO-09731 to the University of Minnesota.