Extraction of the resonance parameters at finite times
arXiv:1007.0860 · doi:10.1016/j.nuclphysb.2010.12.011
Abstract
In this paper we propose a model-independent method to extract the resonance parameters on the lattice directly from the Euclidean 2-point correlation functions of the field operators at finite times. The method is tested in case of the two-point function of the Delta-resonance, calculated at one loop in Small Scale Expansion. Further, the method is applied to a 1+1-dimensional model with two coupled Ising spins and the results are compared with earlier ones obtained by using Luescher's approach.
20 pages, 6 figures