X-Ray and Optical Imagery of the SN 1006 Supernova Remnant
Session 56 -- Supernova Remnants Observation
Display presentation, Thursday, 2, 1994, 9:20-6:30

## [56.09] X-Ray and Optical Imagery of the SN 1006 Supernova Remnant

P.F. Winkler (Middlebury College), K.S. Long (STScI)

X-ray images of two fields from the ROSAT HRI, which together cover the northern half of SN1006, will be presented. Comparison with the radio images by Moffett et al. (1993, AJ, 106, 1566) shows a virtually identical morphology in the northeast, where the shock front is strongest in both bands. New optical images indicate the full extent of non-radiative, optical filaments in the northwestern portion of the shell. These filaments, which mark the present position of the shock front, are remarkably well correlated with the post-shock X-ray emission in this region. The displacement of $10^{\prime\prime}$\ between the optical filaments and the peak X-ray emission, together with previously measured proper motions for the filaments, indicates a timescale of only 30 years for X-ray heating and ionization behind the shock. The X-ray shell is quite thin in this region, suggesting that the plasma is rapidly ionizing through the regime where the 0.5-1.0 keV emissivity is strong. This is exactly what is expected behind a 2400 km~s$^{-1}$ shock, the velocity obtained from the width of the broad H$\alpha$\ line. In addition to the the crisp optical filaments, we find faint, diffuse H$\alpha$\ emission within the remnant shell to the southwest, probably resulting from non-radiative sheets viewed obliquely.