Pion-pion interaction in the I=1 channel

We present preliminary results of a new approach to the study of the pion-pion system in the I=1 channel. The Bethe-Salpeter wave function of the two-pion system is computed on the ground state and the first excited state. From these, we attempt to extract an interaction kernel (potential) which can then be used to extract observables such as the phase shifts. In a first trial, we use rather large pion masses $m_\pi \sim 1.05$ GeV and $m_\pi \sim 0.68$ GeV which do not allow rho decay.