
Alejandro Celis
On SU(2) Chiral Perturbation Theory for K > pi pi Decay
Amplitudes
Abstract
We study the CP conserving decays $K \rightarrow \pi \pi$ using
$SU(2)_L \times SU(2)_R$ Chiral Perturbation Theory (SU(2) ChPT) at
nexttoleading order. The external pions in $K \rightarrow \pi \pi$
are hard, thus complicating the power counting of the theory. However
we provide arguments about the possibility of calculating the pion
chiral logarithms, i.e. the corrections of $O(M^2
\mathrm{log}(M^2))$, for the nonleptonic decay $K \rightarrow \pi
\pi$. A comparison with SU(3) ChPT is done to check our results.
LU TP 0912
