Models of optical and soft x-ray spectra in AM Her stars (open access)

Models of optical and soft x-ray spectra in AM Her stars

The AM Her systems are widely believed to be cataclysmic variable systems in which the white dwarf has a magnetic field strong enough to lock the white dwarf to the companion star. The magnetic field channels the accretion flow to the magnetic polar caps of the white dwarf where the gas passes through a strong shock and the accretion energy is released. The continuum spectra of the AM Her systems have three major components: the ir/optical component, the EUV/soft x-ray component, and the hard x-ray component. Models of the AM Her systems generally agree that the hard x-rays are free-free radiation emitted by the hot postshock gas and that the optical component is electron cyclotron emission from the postshock gas. The soft x-ray component is less well understood, primarily because it is very soft (temperature less than 100 eV) and thus is very difficult to measure accurately with current instruments. Models agree that some soft x-ray emission will arise from hard x-rays and cyclotron radiation that is absorbed at the stellar surface and re-radiated, but other sources of soft x-rays have also been suggested. Thus it is important to develop models for the soft x-ray spectrum. This paper presents some …
Date: May 25, 1987
Creator: Langer, S.H.
System: The UNT Digital Library