Institute for Theoretical Physics
University of Leipzig
04109 Leipzig, Germany
We calculate the vacuum energy in the background of a color magnetic vortex for SU(2) and SU(3). We use zeta functional regularization to obtain analytic expressions suitable for numerical treatment. The momentum integration is turned to the imaginary axis and fast converging sums/integrals are obtained. We investigate numerically a number of profiles of the background in order to find out which configuration minimizes the total energy of the system. In this problem bound states (tachyonic modes) turn out to be present for all investigated profiles making them intrinsically unstable.