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arXiv · 0705.1331

X-ray emissions from two-temperature accretion flows within a dipole magnetic funnel

Curtis J. Saxton·Kinwah Wu·Joao. B. G. Canalle·Mark Cropper·Gavin Ramsay
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Abstract

We investigate the hydrodynamics of accretion channelled by a dipolar magnetic field (funnel flows). We consider situations in which the electrons and ions in the flow cannot maintain thermal equilibrium (two-temperature effects) due to strong radiative loss, and determine the effects on the keV X-ray properties of the systems. We apply this model to investigate the accretion shocks of white dwarfs in magnetic cataclysmic variables. We have found that the incorporation of two-temperature effects could harden the keV X-rays. Also, the dipolar model yields harder X-ray spectra than the standard planar model if white dwarf is sufficiently massive (>~1M_sun). When fitting observed keV X-ray spectra of magnetic cataclysmic variables, the inclusion of two-temperature hydrodynamics and a dipolar accretion geometry lowers estimates for white-dwarf masses when compared with masses inferred from models excluding these effects. We find mass reductions <~9% in the most massive cases.

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Curtis J. Saxton, Kinwah Wu, Joao. B. G. Canalle, Mark Cropper, Gavin Ramsay. 2007-05-09. X-ray emissions from two-temperature accretion flows within a dipole magnetic funnel. https://doi.org/10.1111/j.1365-2966.2007.11958.x

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