相关论文: Charged Kaons at the Main Injector (CKM)
High statistics data for the K+ -> mu+ nu gamma decay can allow the precision determination of the kaon structure dependent form factors and the kaon polarizability. This study is possible at the proposed FNAL CKM experiment. CKM (Charged…
We, the KAMI (Kaons at the Main Injector) collaboration, express our interest to continue the experimental program of rare kaon decay physics at Fermilab using the Main Injector. KAMI's primary physics goals shall be: 1. The first detection…
A decade long search for the rare kaon decay to pi^+nunu-bar has been pursued by E787. Two signal events are observed, giving a measurement of the branching ratio Br(K^+ -> PI^+NUNU-BAR)=1.57^+1.75_-0.82 x 10^-10 and a constraint on the…
The experimental program for the study of the rare kaon decays, K -> pnn, is summarized. A review of recent results is provided along with a discussion of prospects for the future of this program. The primary focus of the world-wide kaon…
ORKA is a proposed experiment to measure the K+ -> pi+ nu nubar branching ratio with 5% precision using the Fermilab Main Injector high intensity proton source. The detector design is based on the BNL E787/E949 experiments, which detected…
ORKA is a proposed experiment to measure the K+ -> pi+nunubar branching ratio with 5% precision using the Fermilab Main Injector high-intensity proton source. The detector design is based on the BNL E787/E949 experiments, which detected…
We report on a search for the rare decay K_L -> pi^0 nu nubar in the KTeV experiment at Fermilab. We searched for two-photon events whose kinematics were consistent with an isolated pi^0 coming from the decay K_L -> pi^0 nu nubar. One…
We discuss the problem of theoretical uncertainties in the combination of observables related to the CKM matrix elements and propose a statistically sensible method for combining them. The overall fit is performed on present data, and…
We present a measurement of R_B, the ratio of the branching fraction for the rare decay D0 -> K+ pi- to that for the Cabibbo-favored decay D0 -> K- pi+. Charge conjugate decays are implicitly included. A signal of 2005 +/- 104 events for…
In the first year of physics run, the E949 experiment at Brookhaven National Laboratory has already collected $1.8\times 10^{12}$ kaons stopping in the target. Additional evidence for the rare charged kaon decay $K^+\to\pi^+\nu\bar{\nu}$…
ORKA is an experiment to observe of order 1000 K+ -> pi+ nu nubar events and to make a precision measurement of the branching fraction. It has been proposed to run at Fermilab using the Main Injector. This note describes ORKA and its…
Precision measurements of the branching ratios (BRs) for rare kaon decays can provide unique constraints on CKM unitarity and may reveal the existence of new physics. The BRs for two of these decays, $K^+\to\pi^+\nu\bar{\nu}$ and…
We have observed 1 event consistent with the signature expected of the rare decay of a positive kaon to a positive pion and a neutrino anti-neutrino pair. In the examined momentum region of 211 to 230 MeV/c in the center of mass of the kaon…
Measured ratios of decay rates for Ke3/K2\pi, K\mu3/K2\pi and K\mu3/Ke3 are presented. These measurements are based on K^+- decays collected in a dedicated run in 2003 by the NA48/2 experiment at CERN. The results obtained are Ke3/K2\pi =…
The Fermilab HyperCP collaboration is making precision studies of charged hyperon and kaon decays, as well as searches for rare and forbidden hyperon and kaon decays. We report here on measurements of the branching ratios of the…
In this talk I describe a proposed Fermilab Main Injector experiment to carry out a program of measurements on the physics of K^0 mesons. The experiment is designed to maximize the interference between K_L and K_S mesons near their…
Using data collected with the HyperCP (E871) spectrometer during the 1997 fixed-target run at Fermilab, we report the first observation of the decay K- -> pi- mu+ mu- and new measurements of the branching ratios for K+/- -> pi+/- mu+ mu- .…
Three events for the decay K+ => pi+,nu,nubar have been observed in the pion momentum region below the K+ => pi+,pi0 peak, 140 < P_pi < 199 MeV/c, with an estimated background of 0.93+-0.17(stat.)+0.32-0.24(syst.) events. Combining this…
The KTeV/E799 experiment at Fermilab has searched for the rare kaon decay KL--> pi0ee. This mode is expected to have a significant CP violating component. The measurement of its branching ratio could support the Standard Model or could…
The branching ratio of the rare decay pi0 -> e+ e- has been measured precisely, using the complete data set from the KTeV E799-II experiment at Fermilab. We observe 794 candidate pi0 -> e+ e- events using K0_L -> 3pi0 as a source of tagged…