## K to ππhadronic matrix elements of left-right current-current operators    [PDF]

Stefano Bertolini, Alessio Maiezza, Fabrizio Nesti
Effective \Delta S=1 four fermion operators involving left- and right-handed currents are relevant in left-right gauge extensions of the standard model and scalar extension of the Yukawa sector. They induce K to \pi\pi\ decays which are strictly constrained by experimental data, typically resulting in strong bounds on the new physics scales or parameters. We evaluate the K to \pi\pi\ hadronic matrix elements of such operators within the phenomenological framework of the Chiral Quark Model. The results are consistent with the estimates used in a previous work on TeV scale left-right symmetry, thus confirming the conclusions obtained there.
View original: http://arxiv.org/abs/1305.5739