ROSAT PSPC Observation of the Supernova Remnant 3C 391

Abstract

view Abstract Citations (40) References (24) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS ROSAT PSPC Observation of the Supernova Remnant 3C 391 Rho, J. -H. ; Petre, R. Abstract The supernova remnant 3C 391 (G3 1.9+0.0) was observed using the ROSAT Position Sensitive Proportional Counter (PSPC). The PSPC image reveals centrally concentrated X-ray emission inside the radio shell, anticorrelated with the radio image. The northwestern half of the remnant has a strong radio shell and weak, centrally concentrated X-ray emission. In contrast, the southeastern half has strong central X-ray emission and weak radio emission. A spectral analysis combining PSPC and Einstein IPC data indicates that the X-ray emission arises from a thermal plasma that has not attained ionization equilibrium, though a nonthermal model can be rejected only with 90% confidence. There is evidence, at the 90% confidence level, of slightly enhanced abundances of the intermediate α-burning elements, Mg, Si, and S. The best-fit NH is 2.4 x 1022 and kT is 0.5 keV (T = 5.9 x 106 K). The centrally concentrated morphology and the probable thermal origin of the X-ray emission along with the radio shell suggest that 3C 391 is similar to W44 and W28. There are spectral variations between the northwestern and southeastern parts of the remnant: either the northwest has higher NH or the southeastern part has lower temperature, the former being more consistent with the X-ray morphology. The difference in NH is large enough to account for the reduced X-ray surface brightness in the northwest, and the density in the northwest is higher than that in the southeastern shell. The X-ray data are consistent with the idea that the progenitor supernova has exploded just inside a molecular cloud, but close to the edge. The northwestern structure is created by the propagation of the supernova shock into the cloud while the enhanced central X-ray emission arises from evaporation of clumps from the edge of the cloud trapped within the remnant. The southeastern radio and X-ray emission represent a "breakout" of the shock into low-density, intercloud material. Publication: The Astrophysical Journal Pub Date: August 1996 DOI: 10.1086/177645 Bibcode: 1996ApJ...467..698R Keywords: SHOCK WAVES; ISM: INDIVIDUAL ALPHANUMERIC: 3C 391; ISM: SUPERNOVA REMNANTS; X-RAYS: ISM full text sources ADS | data products SIMBAD (6) HEASARC (1)