We compute bounce solutions describing false vacuum decay in a Phi**4 modelin two dimensions in the Hartree approximation, thus going beyond the usualone-loop corrections to the decay rate. We use zero energy mode functions ofthe fluctuation operator for the numerical computation of the functionaldeterminant and the Green's function. We thus avoid the necessity ofdiscretizing the spectrum, as it is necessary when one uses numericaltechniques based on eigenfunctions. Regularization is performed in analogy ofstandard perturbation theory; the renormalization of the Hartree approximationis based on the two-particle point-irreducible (2PPI) scheme. The iterationtowards the self-consistent solution is found to converge for some range of theparameters. Within this range we find the corrections to the leading one-loopapproximation to be relatively small, not exceeding one order of magnitude inthe total transition rate.
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