Far-ultraviolet spectrophotometry of supernova remnants - Observations and astrophysical interpretation

Abstract

Far UV spectra obtained with IUE in the supernova remnants Cygnus Loop in the galaxy and N49 and N63 in the LMC have been interpreted using the radiating shock-wave models. Some elemental depletion and a range of shock velocities (approximately 80-130 km/s) are needed to give an adequate description of the observed spectra. Carbon is anomalous, a heavier depletion being required. The weakness of the C II 1335-A line is not understood. The UV continuum appears to be due to the two-photon process in hydrogen, but there is also weak evidence that resonance fluorescent processes involving molecules may have a role to play.