Related papers: Recent Results from the KTeV Experiment
In this talk results of the study of the $D^0 \to \pi^- e^+ \nu$ decay channel, recorded by the BaBar detector at the c.m. energy close to 10.6 GeV, are reported. The branching fraction of this channel is measured relative to the $D^0 \to…
We present a measurement of the relative branching ratio of the decay KL -> pi e nu gamma (Ke3gamma) with respect to KL-> pi e nu (gamma) (Ke3+Ke3gamma) decay. The result is based on observation of 19 000 Ke3gamma and 5.6 x 10^6 Ke3 decays.…
We present a measurement of the ratio R = \Gamma(\keg;\Estar>30\mev,\qstar>20^\circ)$/$\Gamma(\kegf)$ and a first measurement of the direct emission contribution in KL semileptonic decays. The measurement is done at the DAFNE phi-factory…
The branching fraction of the rate decay $B^0 \rightarrow K^{*0}e^+e^-$ in the dilepton mass region from 30 to 1000 MeV$/c^2$ has been measured by the LHCb experiment, using $pp$ collision data, corresponding to an integrated luminosity of…
A sample of 7253 $K^\pm\to\pi^\pm e^+e^-$ decay candidates with 1.0% background contamination has been collected by the NA48/2 experiment at the CERN SPS, which allowed a precise measurement of the form factor, the branching ratio, and the…
We have observed the decay $K_L\to \mu^+\mu^- \gamma \gamma$ at the KTeV experiment at Fermilab. This decay presents a formidable background to the search for new physics in $K_L\to\pi^0\mu^+\mu^-$. The 1997 data yielded a sample of 4…
We present measurements of R_Kl3rad = Gamma(KL->\pi\ell\nu\gamma; Egcm > 10 MeV)/Gamma(KL->\pi\ell\nu), where ell = mu or e, and Egcm is the photon energy in the kaon rest frame. These measurements are based on KL decays collected in 1997…
The first search for the $B_s^0\rightarrow K^-\pi^+\gamma$ decay in the range $796<m(K^-\pi^+)<1800\,\text{MeV/}c^2$ is performed using data from proton-proton collisions collected by the LHCb experiment at centre-of-mass energies of 7, 8,…
The $B \to \pi$ and $B \to K$ transitions involved in hadronic B decays are investigated in a phenomenological way through the framework of QCD factorization. By comparing our results with experimental branching ratios from the BELLE, BABAR…
The $K^+ \to \pi^0 \pi^0 e^+ \nu$ ($K_{e4}^{00}$) decay has been measured with stopped positive kaons for a data sample of 216 events. A comparison of the observed spectra with a Monte Carlo simulation determined the $K_{e4}^{00}$ form…
CP violation due to interference between $K_L$ and $K_S$ decays into $\pi ^+\pi^-\gamma$ is analyzed in the Standard Model. The CP-violating parameter $\epsilon'_{+- \gamma}$, which is the difference between $\eta_{+-\gamma}$ and…
We have perfomed studies of the KL to PI+PI-GAMMA Direct Emission (DE) and Inner Bremsstrahlung (IB) vertices, based on data collected by KTeV during the 1996 Fermilab fixed target run. We find a1/a2 = -0.737 +- 0.034 GeV^2 for the DE…
Results of a study of the $K^+ \rightarrow \pi^{0} e^{+} \nu \gamma $ decay at OKA setup are presented. More than 32000 events of this decay are observed. The differential spectra over the photon energy and the photon-electron opening angle…
A sample of 3120 $K^\pm\to\pi^\pm\mu^+\mu^-$ decay candidates with $(3.3\pm0.7)%$ background contamination has been collected by the NA48/2 experiment at the CERN SPS, allowing a detailed study of the decay properties. The branching ratio…
A sample of $1.3 \times 10^5$ $K^+ \to \pi^0 e^+ \nu \gamma$ candidates with less than 1% background was collected by the NA62 experiment at the CERN SPS in 2017-2018. Branching fraction measurements are obtained at percent relative…
We study the CP conserving and violating contributions to the decay of $\knng$ in the standard model. In our analysis, we use the form factors for $K\to\gamma$ transitions calculated directly in the entire physical range of momentum…
The absolute branching fractions for the decays $D^0 \to K^-e ^+\nu_e$ and $D^0 \to \pi^-e^+\nu_e$ are determined using $7584\pm 198 \pm 341$ singly tagged $\bar D^0$ sample from the data collected around 3.773 GeV with the BES-II detector…
In this paper, we calculate the branching ratios for B^0\to D_s^+\pi^-, B^+\to D_s^+\pi^0, B^0\to D_s^{*+}\pi^- and B^+\to D_s^{*+}\pi^0 decays in the perturbative QCD factorization approach. We find that the calculated branching ratios of…
We report the recent results on rare kaon decays from the NA48/2 experiment. The precise measurement of direct photon emission (DE) in the decay K+- -> pi+- pi0 gamma and its interference (INT), with the INT amplitude being observed for the…
We present a reanalysis of direct CP violation in the decay K_L -> pi^+ pi^- gamma. We point out an existing discrepancy between the theoretical and experimental definitions of epsilon'_{+-gamma}. Adopting the experimental definition of…