Relaxation phenomena at accelaration of rotation of a spherical vessel with helium II and relaxation in pulsars

Measurements of the rotational speed of the PSR 0833 pulsar in Vela and PSR 0531 in the Crab nebula have shown that after a sudden speed-up of their rotation a considerably long relaxation process is observed. According to Pines [1] it is associated with the neutron star's superfluidity predicted by Migdal [2]. The present paper is devoted to an attempt of modelling these processes observing the relaxation motions of liquid helium after sharp changes in the rotational speed of a spherical vessel filled with superfluid liquid.