ππ scattering from a similarity renormalization group perspective

Abstract

A Wilsonian approach based on the similarity renormalization group to ππ scattering is analyzed in the JI = 00, 11 and 02 channels in momentum space up to a maximal center-of-mass energy of s⎯⎯√=1.4 GeV. We identify the Hamiltonian by means of the 3D reduction of the Bethe-Salpeter equation in the Kadyschevsky scheme. We propose a new method to integrate the SRG equations based in the Crank-Nicolson algorithm with a single step finite difference so that isospectrality is preserved at any step of the calculations. We discuss issues on the high momentum tails present in the fitted interactions hampering calculations.