SUPERFLUID CORE ROTATION IN PULSARS .2. POSTJUMP RELAXATIONS

A theory of nonstationary dynamics of neutron star superfluid core rot ation, based on the dynamics of proton vortex clusters is presented. E xact solutions describing the postjump relaxation of the superfluid co mponent of the star are given with allowance for the spatial dependenc e of viscous friction. In this theory, the core is coupled on timescal es of hours to years, rather than the few seconds' coupling time in mo dels where vortex clusters are ignored. An application of the theory t o the postjump relaxations of the Vela pulsar 0833 - 45 shows that, wi thin the standard range of parameters of neutron stars, the postjump r elaxations of Vela can be understood in terms of the dynamics of the s uperfluid core. The model involves contributions to postjump relaxatio ns from a wide range of radii, with relaxation times scaling as the sq uare of the spin period. It is predicted that millisecond pulsars will not show timing irregularities on timescales larger than a few days.