Precise mass and radius values for the white dwarf and low mass M dwarf in the pre‐cataclysmic binary NN Serpentis

  title={Precise mass and radius values for the white dwarf and low mass M dwarf in the pre‐cataclysmic binary NN Serpentis},
  author={Steven G. Parsons and Thomas R. Marsh and C. M. Copperwheat and Vik S. Dhillon and Stuart P. Littlefair and B. T. Gansicke and R. D. G. Hickman},
  journal={Monthly Notices of the Royal Astronomical Society},
Using the high resolution Ultraviolet and Visual Echelle Spectrograph (UVES) mounted on the Very Large Telescope in combination with photometry from the high-speed CCD camera ULTRACAM, we derive precise system parameters for the pre-cataclysmic binary NN Ser. A model fit to the ULTRACAM light curves gives the orbital inclination as i = 89 degrees.6 +/- 0 degrees.2 and the scaled radii, R-WD/a and R-sec/a. Analysis of the He (II) 4686 angstrom absorption line gives a radial velocity amplitude… 

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