On the nature of the 35-day cycle in HZ Her/Her X-1

Abstract

Regular variations of the pulse period of Her X-1 with X-ray flux observed by Fermi-GBM are examined. We argue that these regular variations result from the free precession of the neutron star in Her X-1.

arXiv comment2 figures, to be published in Astronomy Reports

References in corpus (9)

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