ИСТИНА

Rotation of a neutron star with a dipole magnetic field is characterized by two angles, inclination $\alpha$ with respect to the accretion disk or orbital plane, and magnetic angle $\chi$ between the axis of the dipole and the axis of rotation. Magnetospheric accretion leads to rapid alignment of the angular momentum of the neutron star, but its impact upon the magnetic angle is more subtle and depends upon the possible mass accretion rate variations with the phase of the spin period. This is possible if both angles, $\alpha$ and $\chi$, initially strongly deviate from zero. In this case, accretion leads to an increase of the magnetic angle, possibly up to 90deg, on the time scales of alignment of the rotational axis. In combination with pulsar losses that tend to decrease the magnetic angle with a rate strongly dependent on the current value of $\chi$, this effect can form a broad and possibly bimodal distribution in magnetic angles for the observed population of millisecond pulsars.