Ma. Garlick, SIMULATING THE EMISSION-LINE RADIAL-VELOCITY MODULATION IN DISCLESS INTERMEDIATE POLARS, Monthly Notices of the Royal Astronomical Society, 279(3), 1996, pp. 940-948
A code has been developed which simulates the emission line radial vel
ocity modulation expected in a discless intermediate polar, where the
bulk of the accretion flow flips from one magnetic pole to the other t
wice every beat cycle. The situation is found to produce a radial velo
city curve which exhibits a modulation at the beat period, although th
is is not strictly periodic in that it is modified by an intrinsic und
erlying orbital modulation; i.e., the morphology of the beat modulatio
n over one beat cycle depends on the orbital phase. Interestingly, it
is found that, when the resultant velocity curve over one orbital cycl
e is folded on the beat period and binned coarsely, a quasi-sinusoidal
velocity profile can be reproduced, depending on the values chosen fo
r the various free parameters. An important implication of this result
is that the spin period of BG Canis Minoris could indeed be 847 s, an
d is not necessarily 913 s as we had previously concluded. The model i
s also capable of reproducing the modulation seen in the newly discove
red system RXJ1712.6-2414.