  We have detected weak soft X-ray emission from the Pulsar Wind Nebula
trailing the high velocity star PSR 2224+65 (the `Guitar Nebula'). This X-ray
flux gives evidence of \gamma~10^7 eV particles in the pulsar wind and
constrains the properties of the post-shock flow. The X-ray emission is most
easily understood if the shocked pulsar wind is partly confined in the nebula
and if magnetic fields in this zone can grow to near equipartition values.

Astrophysics