Vortex-interface interactions and generation of glitches in pulsars

We show that the crust-core interface in neutron stars acts as a potential barrier to the peripheral neutron vortices approaching the interface in the model in which these are coupled to the proton vortex clusters. This eleme ntary barrier arises because of the interaction of vortex magnetic flux wit h the Meissner currents set up by the crustal magnetic field at the interfa ce. The dominant part of the force is derived from the cluster-interface in teraction, As a result of the stopping of the continuous neutron vortex cur rent through the interface, angular momentum is stored in the superfluid la yers in the vicinity of the crust-core interface during the interglitch per iod. Discontinuous annihilation of proton vortices at the boundary restores the neutron vortex current and spins up the observable crust on short time -scales, leading to a glitch in the spin characteristics of a pulsar.