Abstract
We obtained the radial velocity field of some optical filaments of the SNR W63. We estimated for its expansion velocity values of 35 ± 12 km s-1 and 70 ± 30 km s-1 depending on whether the SNR is thought to be the nonthermal radio source W63 (<1°) or the whole filamentary complex shown on Palomar Plates (∼ 4°) We derived the SNR ratio E0/n0 for both cases and we found upper limits for the pre-shock density. We compared those with the values derived from the available spectroscopic data.
