One-loop corrections to the instanton transition in the two-dimensional   Abelian Higgs model
  We present an evaluation of the fluctuation determinant which appears as a prefactor in the instanton transition rate for the two-dimensional Abelian Higgs model. The corrections are found to change the rate at most by a factor of 2 for 0.4 < M_W/M_H < 2.0. 
J. Baacke and T. Daiber (Dortmund University)