Jk. Li et Dt. Wickramasinghe, ON THE FASTNESS PARAMETER AND THE INNER DISC RADIUS, Monthly Notices of the Royal Astronomical Society, 286(2), 1997, pp. 25-28
Recently we proposed that gas funnelled by magnetic field lines from a
n accretion disc on to a magnetized compact star does not exert a sign
ificant material torque on the star. We show that a consequence of thi
s result is that in rotational equilibrium the true inner disc radius
is significantly smaller than the corotation radius (<(omega)over bar>
(in)/<(omega)over bar>(co) similar or equal to 0.10-0.74).