Casimir interaction of finite-width strings

Within the trln-formalism we investigate the vacuum interaction of cosmic strings and the influence of strings width on this effect. For the massless real scalar field we compute the Casimir contribution into the total vacuum energy. The dimensional-regularization technique is used. It is shown that the regularized Casimir term contains neither the UV-divergences, nor the divergences related with the non-integrability of the renormalized vacuum mean of the energy-momentum tensor.