The Origin of a Possible Pulsar Wind Nebula in the Cygnus Loop

The Cygnus Loop is one of the brightest, nearest (d sim 540pc), and mostextensively studied supernova remnants. There are numerous observationalindications that it originated from a corecollapse supernova whose progenitormass is sim 15,M _odot . Nevertheless, no neutron star related to the remnanthas yet been identified. A thorough {it Suzaku} XIS mapping of the Cygnus Loophas revealed a possible pulsar wind nebula (PWN) in the Loop. We propose a100,ks EPIC observation of the candidate PWN in order to determine whether ornot it is associated with the Cygnus Loop by measuring the neutron star propermotion and the column density to the nebula. This observation also will allow usto perform spectral mapping to characterize the PWN and constrain the neutron star pulse period. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]