Kaon semileptonic decay (K_{l3}) form factors from the instanton vacuum

Abstract

We investigate the kaon semileptonic decay (K_{l3}) form factors within the framework of the nonlocal chiral quark model from the instanton vacuum, taking into account the effects of flavor SU(3) symmetry breaking. We also consider the problem of gauge invariance arising from the momentum-dependent quark mass in the present work. All theoretical calculations are carried out without any adjustable parameter, the average instanton size (rho ~ 1/3 fm) and the inter-instanton distance (R ~ 1 fm) having been fixed. We also show that the present results satisfy the Callan-Treiman low-energy theorem as well as the Ademollo-Gatto theorem. Using the K_{l3} form factors, we evaluate relevant physical quantities. It turns out that the effects of flavor SU(3) symmetry breaking are essential in reproducing the kaon semileptonic form factors. The present results are in a good agreement with experiments, and are compatible with other model calculations.

12 pages, 3 figures, submitted to PRD

References in corpus (4)

• The leading-twist pion and kaon distribution amplitudes from the QCD instanton vacuum
• Magnetic susceptibility of the QCD vacuum
• Leading-twist pion and kaon distribution amplitudes in the gauge-invariant nonlocal chiral quark model from the instanton vacuum
• QCD condensates with flavor SU(3) symmetry breaking from the instanton vacuum

Cited by in corpus (5)

• Rare meson decays into very light neutralinos
• Electromagnetic form factors of the pion and kaon from the instanton vacuum
• 1/N_c corrections to the magnetic susceptibility of the QCD vacuum
• Spin structure of the pion from the instanton vacuum
• Heavy-light quark systems from the QCD instanton vacuum: $N_f=1$ light flavor case