Exploring the X-ray emission properties of the supernova remnant G67.7+1.8 and its central X-ray sources
Abstract
We have studied the supernova remnant G67.7+1.8 with the Chandra X-ray observatory. The remnant's X-ray morphology correlates well with the double-arc structure seen at radio wavelength. The X-ray spectra of the northern and southern rim of G67.7+1.8 exhibit emission line features of highly ionized metals, which suggests that most of the observed X-rays originate in a thermal plasma. We find magnesium, silicon, and sulphur are overabundant relative to the solar values. Gaussian emission lines at 4 keV and 7 keV are detected. The 4 keV line is consistent with K-emission lines from 44Ca and/or 44Sc whereas the 7 keV line feature may arise from unresolved Fe-K lines. Chandra's sub-arcsecond angular resolution allowed us to detect four faint point sources located within 1.5 arc-minutes of the geometrical remnant center. Among these objects, CXOU195424.75+312824.9 and CXOU195429.82+312834.1 do not have optical counterparts, leaving them as candidates for a possible compact stellar remnant.