相关论文: Recent Results from KTeV
Preliminary KTEV results are presented based on the 1997 data set, and include an improved measurement of Re(e'/e), CPT tests, and precise measurements of Tau_S and Delta M.
Data from the KTeV experiment have provided many opportunities for studies of fundamental symmetries in nature, not just CP. We present new limits on the lepton flavor violating decays K_L -> pi0 mu e, K_L -> pi0 pi0 mu e and pi0 -> mu e.…
This presentation reports on the first experimental search for the decay Klong to $\pi^0 \pi^0 \mu^+ \mu^-$ based on data collected by the KTeV experiment. Although this decay mode is possible within the standard model, its rate is phase…
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…
The KTeV experiment has carried out a broad program of studies of rare kaon decays. In this paper we present results on KL -> pi0 gamma gamma, KL -> pi0 e+ e- gamma and KL -> pi0 pi0 gamma. These decays provide a window for testing chiral…
Experimental and theoretical progress concerning the rare decay pi0 to e+e- is briefly reviewed. It includes the latest data from KTeV and a new model independent estimate of the decay branching which show the deviation between experiment…
We report on a new measurement of the decay KL -> pi0 gamma gamma by the KTeV experiment at Fermilab. We determine the KL -> pi0 gamma gamma branching ratio to be (1.68 +/- 0.07 +/- 0.08)x10**-6. Our data shows the first evidence for a…
Recent results are presented for (1) the charge asymmetry in semielectronic kaon decay; (2) the charge radius of the neutral kaon; (3) the decay Klong -> pi0 pi0 e+e-; (4) constraints on rho(CKM) from kaon decays; (5) lepton flavor…
We report on a new measurement of the branching ratio B(KL->pi0 gamma gamma)using the KTeV detector. We reconstruct 1982 events with an estimated background of 608, that results in B(KL -> pi0 gamma gamma) = (1.29 +/- 0.03(stat) +/-…
The recent progress in search for T-violating transverse muon polarization in the decays K^+ --> pi^0 mu^+ nu and K^+ --> mu^+ nu gamma in the on-going experiment E246 at KEK is reported. Future prospects in polarization measurements are…
In this talk I will review the recent experimental status of $\sigma(e^+ e^- \to hadrons)$ at $\sqrt{s}<10 GeV$ and the prospects for the future. The influence on $\alpha_{QED}(M^2_{Z})$ and $(g-2)_{\mu}$ is also discussed.
We report on a new measurement of the branching ratio B(KL -> pi0 e+ e- gamma) using the KTeV detector. This analysis uses the full KTeV data set collected from 1997 to 2000. We reconstruct 139 events over a background of 14, which results…
The recent discovery of a large CP violating asymmetry in K(L) --> PI+ PI- E+ E- mode has prompted us to seach for the associated K(L) --> PI0 PI0 E+ E- decay mode in the KTeV-E799 experiment at Fermilab. In 2.7E+11 K(L) decays, one…
A new result for the transverse mu^+ polarization, P_T, in the decay K^+ --> pi^0 mu^+ nu has been obtained in the KEK E246 experiment. Combined with our earlier result, P_T = (-1.12 +- 2.17(stat) +- 0.90(syst))x10^{-3} and Im(\xi) = (-0.28…
The analysis of hyperon semi-leptonic decay data is addressed with reference to SU(3) breaking and isospin mixing between Lambda^O and Sigma^O. Various approaches to SU(3) breaking are discussed and compared. The phenomenological…
We report on the first observation of the decay KL -> pi0 ee gamma by the KTeV E799 experiment at Fermilab. Based upon a sample of 48 events with an estimated background of 3.6 +/- 1.1 events, we measure the KL -> pi0 ee gamma branching…
This talk discusses possible new physics interpretations of recent experimental results on the B-->K*mu+mu- decay that show a discrepancy with the Standard Model predictions. A model independent analysis that takes into account all the…
I will here make some brief comments on the T- and CP- odd asymmetry observed by KTeV in the KL -> pi^+pi^-e^+e^- decay.
We summarize recent b -> s mu mu results from the CDF experiment based on the full 9.6 fb-1 dataset collected in p-pbar collisions at sqrt(s) = 1.96 TeV. The decays analyzed are; B+ -> K+ mu+ mu-, B0 -> K*0(892) mu+ mu-, B0 -> K0_s mu+ mu-,…
A systematic analysis of New Physics impacts on the rare decays KL to pi0 l+ l- is performed. Thanks to their different sensitivities to flavor-changing local effective interactions, these two modes could provide valuable information on the…