Open AccessTwo‐temperature accretion flows in magnetic cataclysmic variables: structures of post‐shock emission regions and X‐ray spectroscopy
Author(s) -
Saxton Curtis J.,
Wu Kinwah,
Cropper Mark,
Ramsay Gavin
Publication year - 2005
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1111/j.1365-2966.2005.09103.x
Subject(s) - white dwarf , physics , astrophysics , accretion (finance) , intermediate polar , electron temperature , magnetic field , effective temperature , spectral line , cataclysmic variable star , radiative transfer , ion , astronomy , stars , quantum mechanics
We use a two‐temperature hydrodynamical formulation to determine the temperature and density structures of the post‐shock accretion flows in magnetic cataclysmic variables (mCVs) and calculate the corresponding X‐ray spectra. The effects of two‐temperature flows are significant for systems with a massive white dwarf and a strong white‐dwarf magnetic field. Our calculations show that two‐temperature flows predict harder keV spectra than one‐temperature flows for the same white‐dwarf mass and magnetic field. This result is insensitive to whether the electrons and ions have equal temperature at the shock, but depends on the electron–ion exchange rate, relative to the rate of radiative loss along the flow. White‐dwarf masses obtained by fitting the X‐ray spectra of mCVs using hydrodynamic models including the two‐temperature effects will be lower than those obtained using single‐temperature models. The bias is more severe for systems with a massive white dwarf.