Related papers: Radiative and rare kaon decays : an update
We discuss the theory prediction of epsilon_K and the rare K -> pi nu nu-bar decays and review the structure and current status of higher-order contributions to these flavour changing processes in the standard model in some detail. This…
Recent results on charged rare kaon decays from the NA48/2 Collaboration and on neutral kaon decays from the KLOE Collaboration will be reviewed.
Rare K decays are an important testing ground of the electroweak flavour theory. They can provide new signals of CP-violation phenomena and, perhaps, a window into physics beyond the Standard Model. The interplay of long-distance QCD…
We have observed the rare decay K+ --> pi+ mu+ mu- and measured the branching ratio Gamma(K+ --> pi+ mu+ mu-)/Gamma(K+ --> all) = (5.0 +/- 0.4 (stat.) +/- 0.7 (sys.) +/- 0.6 (theor.)) x 10^{-8}. We compare this result with predictions from…
We perform a chiral one-loop calculation of the unitarity corrections to the processes K+ -> pi+ gamma l+l- up to O(E^6), taking into account pi+pi- intermediate states. Branching ratios and differential branching ratios are computed and…
Rare kaon decays offer a powerful tool for investigating new physics in $s\to d$ transitions. Currently, many of the interesting decay modes are either measured with rather large uncertainties compared to their theoretical predictions or…
The importance of rare $K$ decays especially in the context of a kaon unitarity triangle (KUT) is emphasized. The decay $K_L \to \pi^0 \nu \bar \nu$ is theoretically very clean but experimentally extremely challenging. The Standard Model…
We survey the possibilities of detecting the $s \rightarrow d \gamma$ transition in kaon and hyperon radiative decays. In the more frequent decays, like $K^+ \rightarrow \pi^+ \pi^o \gamma$, $K^+ \rightarrow \pi^+ \ell^+ \ell^-$, the…
This paper reviews the current status of experimental measurements of radiative kaon decays. Several experiments at BNL, CERN and FNAL have recently or will soon complete data collection; as a result, several new results are available.
In this talk, we present our recent work on the $K\ra\pi \bar{l} l$ decays in a combined framework of chiral perturbation theory and Large--$N_c$ QCD under the dominance of a minimal narrow resonance structure. The proposed description…
The neutral Kaon decays Ks->gamma gamma and Kl->pi0 gamma gamma are very sensitive to higher order loop effects of Chiral Perturbation Theory (ChPT). New measurements of the NA48 experiment show that ChPT contributions of O(p^6) cannot be…
The rare kaon decay K^+ --> \pi^+ \nu \bar{\nu} is considered in the framework of the models based on the SU(3)_C X SU(3)_L X U(1)_N (3 - 3 - 1) gauge group. It is shown that a lower bound of the Z' mass in the 3 - 3 - 1 model with…
The rare decay KL to pi0mu+mu- has a significant CP-conserving contribution. The reliable theoretical estimation of this piece from the experimental pi0-two photon branching ratio is shortly reviewed. Then, we discuss the exceptional…
We present a concise review of the theoretical status of rare K -> pi nu nubar decays in the standard model (SM). Particular attention is thereby devoted to the recent calculation of the next-to-next-to-leading order (NNLO) corrections to…
Results from BABAR's full dataset are presented for the angular analysis of the rare decay B -> K*l+l-, where l represents an electron or muon, including measurements of the longitudinal K* polarization and the lepton forward-backward…
We summarize the latest BABAR results on B -> K(*) l+l- and B -> rho (omega) gamma
The new experimental data of kaon photoproduction on the nucleon, gamma p -> K+ Lambda, have been analyzed by means of a multipoles model. Different from the previous models, in this analysis the resonance decay widths are constrained to…
We review the status of theory and experiment of very rare and forbidden kaon decays. We then review the radiative non-leptonic decays, and the associated Dalitz pair modes. We pay particular attention to the study of long distance physics…
Using the most general, model independent form of the effective Hamiltonian rare decays (B -> l^+ l^- gamma (l=mu, tau)) are studied. The sensitivity of the photon energy distribution and branching ratio to the new Wilson coefficients is…
After a decade of no measurements of pion and muon rare decays, PIBETA, a new experimental program is producing its first results. We report on a new experimental study of the pion beta decay, Pi(+) -> Pi(0) e(+) Nu, the Pi(e2 gamma)…