THE NOISE IN THE 35-D CYCLE OF HER X-1

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1993-11-15

Author

Baykal, Altan
DEETER, JE
SCOTT, DM

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We calculate the power density spectrum of fluctuations in the X-ray turn-on times of Her X-1, including new data which extend the X-ray and optical flux observations to a span of over 20 yr with 221 distinct 35-d high-low flux cycles. If we assume that turn-on times define the period of the 35-d clock, this statistical interpretation of turn-on behaviour is consistent with a white-noise process in the first derivative of the 35-d phase fluctuations (or a random walk in clock phase). We discuss the implications of considering the 35-d clock mechanism as a noise process.

Subject Keywords

Methods, statistical, Binaries, close, Stars, individual, her x-1, X-rays, stars

URI

https://hdl.handle.net/11511/47691

Journal

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY

DOI

https://doi.org/10.1093/mnras/265.2.347

Collections

Department of Physics, Article

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Citation Formats

A. Baykal, J. DEETER, and D. SCOTT, “THE NOISE IN THE 35-D CYCLE OF HER X-1,” MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, pp. 347–350, 1993, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/47691.