K_S\rightarrow γγ, K_L\rightarrowπ^0γγ$ and Unitarity

Abstract

Agreement between the experimental value $\Gamma (K_S\to \gamma \gamma )$ and the number predicted via a one-loop chiral perturbation theory calculation has been cited as a success for the latter. On the other hand the one-loop prediction for the closely related process $K_L\to {\pi }^0\gamma \gamma$ has been found to be a factor three below the experimental value. Using the inputs of unitarity and dispersion relations, we demonstrate the importance of higher order loop effects to both of these processes.

20 pages (4 figures available on request), UMHEP-397

References in corpus (1)

• Photon-Photon Scattering, Pion Polarizability and Chiral Symmetry

Cited by in corpus (26)

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• $\Delta I=1/2$ rule for kaon decays derived from QCD infrared fixed point
• Vector meson exchange contributions to K --> pi gamma gamma and K(L) -> gamma lepton+ lepton-
• Precise measurement of the decay $K_L\to {\pi }^0\gamma \gamma$
• Reanalysis of the decay K_L -> pi0 e+ e-
• Search for the Decay D0 -> gamma gamma and Measurement of the Branching Fraction for D0 -> pi0 pi0
• The Rare Decay D^0 -> gamma gamma
• Precise measurements of the KS->gamma gamma and KL->gamma gamma decay rates
• Vector-meson contributions do not explain the rate and spectrum in K_L -> pi0 gamma gamma
• Unitarity corrections to K+ -> pi+ gamma l+l-
• K_L -> pi0 gamma gamma and the bound on the CP-conserving K_L -> pi0 e+e-
• Dispersive treatment of $K_S\to \gamma \gamma$ and $K_S\to \gamma {\ell }^{+}{\ell }^{-}$
• Recent developments in rare kaon decays
• Facets of chiral perturbation theory
• Role of Scalar Meson Resonances in $K_{L}^{0} \rightarrow π^{0} γγDecay
• Chiral predictions for K_L -> pi0 gamma mu+ mu-
• Measurement of the KS->gg branching ratio using a pure KS beam with the KLOE detector
• Kaon Weak Decays in Chiral Theories
• Leading Chiral Logarithms of $K_S\to \gamma \gamma$ and $K_S\to \gamma l^{+}{l}^{-}$ at two Loops
• Theoretical overview of kaon decays
• Mirror matter admixtures in K_S to gamma gamma
• On the electron-positron energy asymmetry in K_L --> pi0 e+ e-
• Status of chiral perturbation theory