Radio pulsars observed at X-ray energies by the X-ray timing explorer

The Rossi X-Ray Timing Explorer observed a number of X-ray emitting radio pulsars soon after launch on 30 Dec. 1995. These included two plerionic systems formed in recent supernova events, the Crab Nebula with its 33 ms pulsar PSR 0531+21 and MSH 15-52 with its 151 ms pulsar PSR 1509-58. Observations of these sources for 20–30 ksec with both the PCA and HEXTE allowed precision phase resolved spectroscopy for the Crab Nebula, confirmation of the light curve and pulsed spectrum for PSR 1509-58, and separation of the Nebular emissions from the pulsed X-rays over the 18–250 keV range for both sources. Within statistical uncertainties, a power law spectrum fits all the observations over this limited energy range. The nebular region for both sources has a photon index of about −2.1, while the pulsed spectra are considerably harder. Significant differences in spectral index are observed for the first pulse, the second pulse, and the interpulse of PSR 0531+21.