84
Models
€Four models exist for these systems
a)Intermediate Polar
Motch
et al (1996)
Norton
et al (2002)
Motch
et al (1996)Norton
et al (2002)b)Double Degenerate PolarCropper et al (1998)
Cropper et al (1998)c)Double Degenerate AlgolMarsh & Steeghs
(2002)
Ramsay
et al (2002)
Marsh & Steeghs
(2002)Ramsay
et al (2002)d)Electric StarWu et
al (2002)
Wu et
al (2002)€Of these models, three involve magnetic
fields
€Neutron star models are ruled out because of the
absence of a hard tail of X-ray emission; also they
need to be extremely close
(too close for the observed level of reddening)
absence of a hard tail of X-ray emission; also they
need to be extremely close
(too close for the observed level of reddening)