Nonthermal X‐Ray Emission from the Shell‐Type Supernova Remnant G347.3−0.5

Recent ASCA observations of G347.3-0.5, an SNR discovered in the ROSATAll-Sky Survey, reveal nonthermal emission from a region along the northwesternshell (Koyama et al. 1997). Here we report on new pointed ASCA observations ofG347.3-.5 which confirm this result for all the bright shell regions and alsoreveal similar emission, although with slightly different spectral properties,from the remainder of the SNR. Curiously, no thermal X-ray emission is detectedanywhere in the remnant. We derive limits on the amount of thermal emittingmaterial present in G347.3-0.5 and present new radio continuum, CO and infraredresults which indicate that the remnant is distant and of moderate age. We showthat our observations are broadly consistent with a scenario that has most ofthe supernova remnant shock wave still within the stellar wind bubble of itsprogenitor star, while part of it appears to be interacting with densermaterial. A point source at the center of the remnant has spectral propertiessimilar to those expected for a neutron star and may represent the compactrelic of the supernova progenitor.Comment: LaTeX, 9 pages, 8 figures (5 PS, 3 jpg), uses emulateapj.sty. Accepted for publication in Ap