Simulations of Supernova Remnants in Diffuse Media. II. Three Remnants and Their X-Ray Emission

This paper describes the X-ray emission from supernova remnants evolving in warm, low density, nonthermal pressure dominated regions. Non-equilibrium ionization hydrocode simulations are used to predict the high resolution spectra, ROSAT PSPC countrates, spatial appearance, color temperatures, and the O VII and O VIII emission line fluxes as a function of time. For comparisons with observations, this paper also applies the standard observational analyses for determining the color temperature, electron density, and thermal pressure to ROSAT ``observations'' of one of the simulated remnants, thus providing a map between observational results and physical conditions. The simulated remnants' C IV, N V, and O VI column densities are also reported. The simulations are applied to studies of the Galactic halo and Local Bubble and additionally may be of interest to studies of external galaxies and Galactic interarm regions.