On the 9.25 minute X ray oscillations of V471 Tauri

  • Edward M. Sion
Cataclysmic Variables
Part of the Lecture Notes in Physics book series (LNP, volume 274)


The 9.25 minute x ray oscillations discovered recently by K. Jensen (1985) in V471 Tauri using EXOSAT, arise from the DA2 white dwarf (Jensen, et al. 1986). One possible explanation of the oscillations is x ray modulation due to a rotating, magnetized, accreting degenerate (Jensen, et al 1986). The results of model calculations of accretion and diffusion of wind/flare material onto the V471 Tau white dwarf are presented as a test of this interpretation. Weak line features constrain the field if they arise from a polar accretion area. It is shown that rotational modulation of x-ray, opaque accretion poles is probably may not be the correct explanation unless the white dwarf is strongly magnetic, accreting matter at a rate of 10-−15M yr. −1, but has much larger polar accretion areas than that obtained from kinematical models of the accretion flow.


Accretion Rate White Dwarf Accretion Flow International Ultraviolet Explorer Radiative Acceleration 
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Copyright information

© Springer-Verlag Berlin Heidelberg 1987

Authors and Affiliations

  • Edward M. Sion
    • 1
  1. 1.Department of Astronomy and AstrophysicsVillanova UniversityVillanovaU.S.A.

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