Phase Evolution of the Crab Pulsar between Radio and X-Ray

A study of the Crab pulsar reveals that its X-ray and radio phases exhibit strong correlations, suggesting that timing noise in both bands originates from the pulsar's spin rather than unique physical processes or interstellar medium variations. Analyzing 11 years of X-ray data from the Rossi X-ray Timing Explorer and 6 years of radio observations from the Nanshan Telescope, researchers found no detectable secular change in the distance between emission regions. This challenges the notion that timing noise arises from distinct mechanisms in radio or X-ray emitting regions, aligning with multi-frequency radio observations of PSR B1540−06.

Yan, L. L., Ge, M. Y., Yuan, J. P., Zheng, S. J., Lu, F. J., Tuo, Y. L., Tong, H., Zhang, S. N., Lu, Y., Han, J. L., & Du, Y. J. (2017). Phase Evolution of the Crab Pulsar between Radio and X-Ray. The Astrophysical Journal, 845(2), 119. https://doi.org/10.3847/1538-4357/aa7ff6