English

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

Astrophysics 2019-08-19 v1

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.

Keywords

Cite

@article{arxiv.0705.1331,
  title  = {X-ray emissions from two-temperature accretion flows within a dipole magnetic funnel},
  author = {Curtis J. Saxton and Kinwah Wu and Joao. B. G. Canalle and Mark Cropper and Gavin Ramsay},
  journal= {arXiv preprint arXiv:0705.1331},
  year   = {2019}
}
R2 v1 2026-06-21T08:26:42.698Z