On the I = 2 channel π-π interaction in the chiral limit

Abstract

An approximate local potential for the residual π + -π + interaction is computed. We use an O(a 2 ) improved action on a coarse 9 3 × 13 lattice with a ≈ 0.4fm. The results present a continuation of previous work: Increasing the number of gauge configurations and quark propagators we attempt extrapolation of the π + -π + potential to the chiral limit.

Progress in kaon physics on the lattice

“…Of course, this takes enormous amount of computing resources because we need to take a large number of momenta in order to get a few low eigenvalues, and the signal gets poor as we insert the pion momentum. A number of lattice groups applied this method to the I = 2 elastic pion scattering problem [39,40]. One way to get around the Maiani-Testa theorem is to modify the boundary condition (BC) for the pions [41].…”

Exploring the π + -π + Interaction in Lattice QCD

“…I , defined through (22), comprises all sources of the residual interaction, be it from gluonic correlations, or quark exchange (or quark-antiquark loops, if the simulation is unquenched).…”

“…Preliminary stages of this work have been reported before [22,23]. A self-contained presentation of the formalism, in section 2, and a discussion and interpretation of the lattice results, in section 3, are the purpose of this paper.…”