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arXiv · 1808.04240

Time evolution of the X-ray and gamma-ray fluxes of the Crab pulsar

L. L. Yan·M. Y. Ge·F. J. Lu·S. J. Zheng·Y. L. Tuo·Z. J. Li·L. M. Song·J. L. Qu
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Abstract

We studied the evolution of the X-ray and gamma-ray spectra of the Crab pulsar utilizing the 11-year observations from the Rossi X-ray Timing Explorer (RXTE) and 9-year observations from the Fermi Gamma-ray Space Telescope (FGST). By fitting the spectrum of each observation, we obtained the corresponding flux, and then analysed the long term evolution of the X-ray (or gamma-ray) luminosities as well as their correlations with the spin down power of the pulsar. The X-ray flux in 5-60 keV obtained by the Proportional Counter Array (PCA) of RXTE decreases with a rate of (-2.4+/-0.4)*10^(-14) erg cm^(-2) s^(-1) per day. The X-ray flux in 15-250 keV obtained by the High Energy X-ray Timing Experiment (HEXTE) of RXTE and the gamma-ray flux in 0.1-300 GeV by the Large Area Telescope (LAT) onboard FGST show similar decreasing trend, but are unsignificant statistically. The 5--60 keV X-ray luminosity L_(X) is correlated with the spin down power L_(sd) by L_(X) propto L_(sd)^(1.6+/-0.3), which is similar to the statistical results for young pulsars.

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L. L. Yan, M. Y. Ge, F. J. Lu, S. J. Zheng, Y. L. Tuo, Z. J. Li, L. M. Song, J. L. Qu. 2018-08-08. Time evolution of the X-ray and gamma-ray fluxes of the Crab pulsar. https://doi.org/10.3847/1538-4357/aad911

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