Quenched Chiral Perturbation Theory for Weak Interactions

por Elisabetta Pallante (Universitat de Barcelona)

jueves 4 mar. 1999 12:00 → 13:00 Europe/Madrid

Sala Seminarios (Dpto. de Fisica Teorica (UVEG))

Chiral Perturbation Theory (ChPT) combined with lattice QCD is a promising tool for computing hadronic weak matrix elements at long distances. Here I discuss the derivation of the one loop generating functional of ChPT in the presence of weak interactions with $\vert\Delta S\vert =1,\, 2$ and the modifications induced by the {\em quenched} approximation adopted on the lattice. As an immediate application, the full and quenched behaviours of the chiral logarithms which appear in $K\to\pi\pi$ matrix elements can be studied both for $\Delta I=1/2$ and $3/2$.