X-ray Spectrum and Pulsations of the Vela Pulsar
Abstract
We report the results of the spectral and timing analysis of observations of the Vela pulsar with the Chandra X-ray Observatory. The spectrum shows no statistically significant spectral lines in the observed 0.25--8.0 keV band. It consists of two distinct continuum components. The softer component can be modeled as either a magnetic hydrogen atmosphere spectrum with kT = 59 +- 3 eV, R = 15.5 +- 1.5 km, or a standard blackbody with kT = 129 +- 4 eV, R = 2.1 +- 0.2 km (the radii are for a distance of 250 pc). The harder component, modeled as a power-law spectrum, gives photon indices depending on the model adopted for the soft component: gamma = 1.5 +- 0.3 for the magnetic atmosphere soft component, and gamma = 2.7 +- 0.4 for the blackbody soft component. Timing analysis shows three peaks in the pulse profile, separated by about 0.3 in phase. Energy-resolved timing provides evidence for pulse profile variation with energy. The higher energy (E > 1.8 keV) profile shows significantly higher pulsed fraction.
Keywords
Cite
@article{arxiv.astro-ph/0112164,
title = {X-ray Spectrum and Pulsations of the Vela Pulsar},
author = {D. Sanwal and G. G. Pavlov and O. Y. Kargaltsev and G. P. Garmire and V. E. Zavlin and V. Burwitz and R. N. Manchester and R. Dodson},
journal= {arXiv preprint arXiv:astro-ph/0112164},
year = {2007}
}
Comments
4 pages, 2 figures, To appear in "Neutron Stars in Supernova Remnants" (ASP Conference Proceedings), eds P. O. Slane and B. M. Gaensler Corrected TYPOS