The X-ray nebula around PSR 1509-58.

With the use of measured spectra and a model, volumes and luminosities are derived for several components of the supernova remnant MSH 15 - 52. The hard, featureless spectrum and spatial symmetry of the X-ray nebula surrounding the central pulsar strongly indicate synchrotron radiation as the source of emission. Power requirements are easily supplied by the pulsar. The observed surface brightness is only 0.00002 that of the X-ray synchrotron emission around the Crab pulsar, and the X-ray luminosity is 0.01 that of the Crab. In spite of the great difference in luminosity and size, the two systems are probably similar in nature, with the high brightness and unique appearance of the Crab synchrotron nebula being due to the high energy output of the pulsar and the relatively small volume of the confining filaments.