BOUND-STATES AND INSTABILITIES OF VORTICES

We examine the spectrum of small perturbations around global and local (gauge) Abelian vortices, using simple numerical matrix techniques. T he results are of interest both for cosmic strings and for their conde nsed matter analogues, superfluid and superconductor vortices. We tabu late the instabilities of higher winding number vortices, and find sev eral bound states. These localized coherent oscillations of the order parameter can be thought of as particle states trapped in the core of the string.