An X-ray search for pulsar wind nebulae in supernova remnant shells

We propose to observed two pulsar wind nebula (PWN) candidates, serendipitouslydiscovered in a AO4 XMMNewton survey on nonthermal supernova shells, for whichthe existing data are insufficient to draw any firm conclusion. Contrary toclassical PWNe, our two targets are located a the rim of the shells and seems tohave elliptical morhpology indicative of bow shocks. If their plerionic naturewill be confirmed, they will add to the emerging class of high velocity pulsars,providing a natural reason to explain the lack of pulsarSNR associations inother Xray surveys. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]