ROSAT all-sky survey map of the Cygnus Loop: Overall structure and comparison with radio map

The Cygnus Loop is one of the largest and nearest supernova remnants. It was observed by the PSPC detector of the Röntgen-Satellite ROSAT during the survey phase of the ROSAT mission. This has resulted in the highest–sensitivity complete x-ray image of the Cygnus Loop. It also has the high spatial resolution of one arcmin and contains spectral information. It is thus the best map of the Cygnus Loop for studying the overall spatial and spectral structure of its x-ray emission. The Cygnus Loop shows x-ray emission from a more extensive region than previously appreciated, including the south “blowout” region and a newly detected west “bubble”. Significant fine scale spectral variations are detected. The structure of the Cygnus Loop in x-rays is compared to the radio structure recently observed at 1420 MHz with one arcmin resolution using the synthesis telescope of the Dominion Radio Astrophysical Observatory.