Isospin Breaking in $K_{\ell 4}$ Decays of the Neutral Kaon

Abstract

In the presence of photons, the neutral $K_{\ell 4}$ decay, $K^0\to {\pi }^0{\pi }^{-}{\ell }^{+}{\nu }_{\ell }$, can be parameterized in terms of three vectorial, one anomalous, and one tensorial form factors. We present here analytic expressions of two vectorial form factors, $f$ and $g$, calculated at one-loop level in the framework of chiral perturbation theory based on the effective Lagrangian including mesons, photons, and leptons. These expressions may then be used to disentangle the Isospin breaking part from the measured form factors and hence improve the accuracy in the determination of $\pi \pi$ scattering parameters from $K_{\ell 4}$ experiments.

62 pages, LaTeX, 5 postscript figures, 1 table

References in corpus (5)

• Big Bang Nucleosynthesis (in "The Review of Particle Properties" 2004)
• Reduction of one-loop tensor 5-point integrals
• Techniques for the calculation of electroweak radiative corrections at the one-loop level and results for W-physics at LEP200
• High statistics measurement of Ke4 decay properties
• DIRAC: A High Resolution Spectrometer for Pionium Detection

Cited by in corpus (6)

• Kaon Decays in the Standard Model
• Four-point correlator constraints on electromagnetic chiral parameters and resonance effective Lagrangians
• Isospin breaking in the phases of the Ke4 form factors
• Virtual Photon Correction to the $K^{+}\to {\pi }^{+}{\pi }^0{\pi }^0$ Decay
• Splitting Strong and Electromagnetic Interactions in K(L4) Decays
• Size of Isospin Breaking in Charged K(L4) Decay