Hot Gas in the Wolf-Rayet Bubble NGC 6888

The fast stellar winds from WolfRayet (WR) stars sweep up the circumstellarmedia and form the socalled windblown bubbles or WR bubbles. The shock ofthese fast stellar winds against the dense shells left by previous evolutionarystages is expected to produce gas at Xrayemitting temperatures. However,diffuse Xray emission has been detected only inside two WR bubbles: S308 andNGC 6888. Our 100 ks Chandra ACISS observation of the northwest quadrant of NGC6888 presents the first highresolution image and clean spectrum of its diffuseXray emission. To obtain a global view of the physical structure of NGC 688, wehere request a 60 ks XMMNewton observation, which will otherwise take Chandra300 ks for a similar mapping of the entire nebula. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]