$K_{l4}$ - Decays Beyond One Loop

J. Bijnens; G. Colangelo; J. Gasser

doi:10.1016/0550-3213(94)90634-3

paper

$K_{l 4}$ - Decays Beyond One Loop

arXiv:hep-ph/9403390 · doi:10.1016/0550-3213(94)90634-3

Abstract

The matrix elements for $K \to I ¨ I ¨ A ˚ I^½$ decays are described by four form factors $F, G, H$ and $R$ . We complete previous calculations by evaluating $R$ at next-to-leading order in the low-energy expansion. We then estimate higher order contributions using dispersion relations and determine the low-energy constants $L_{1}, L_{2}$ and $L_{3}$ from data on $K_{e 4}$ decays and on elastic pion scattering. Finally, we present predictions for the slope of the form factor $G$ and for total decay rates.

31 pages, LaTex, 3 figs. (two figures appended as postscript file), BUTP-94/4,ROMF2 94/05

Kl4​ - Decays Beyond One Loop

Abstract

$K_{l 4}$ - Decays Beyond One Loop