Nonthermal radio emission from the precataclysmic binary system V471 Tauri

Recent observations have presented strong evidence for the existence of ecl ipses in the nonthermal radio emission from the precataclysmic binary syste m V471 Tau. In this paper we calculate the gyrosynchrotron emission from mo dels assuming a dipole-shaped magnetosphere and a magnetized wind around, t he K dwarf. The model assumes that: electrons are accelerated to mildly rel ativistic energies:in the region where the magnetic fields of the two stars interact and become trapped in the K dwarfs magnetosphere. Comparison with the data indicates that azimuthal drift and energy loss lead to a region o f enhanced density of mildly relativistic electrons, extending for over 100 degrees in azimuth and preceding the white dwarf in phase. The data is bes t fitted by models assuming a power-law drop with azimuthal angle of this e nhancement in mildly relativistic electron density.