相关论文: Measurement of the Muon Decay Parameter delta
We examine the pion exchange mode of neutrinoless double beta decay induced by the R-parity violating quark-lepton operators of the supersymmetric (SUSY) extensions of the standard model of the electroweak interactions. The corresponding…
We report the first measurement of the $D^{\ast -}$ meson polarization in the decay $B^0 \to D^{*-} \tau^+\nu_{\tau}$ using the full data sample of 772$\times 10^6$ $B\bar{B}$ pairs recorded with the Belle detector at the KEKB…
The muon g-2 collaboration has measured the anomalous magnetic g value of the positive muon to within a relative uncertainty of 0.7 parts per million. The result, a_{\mu^+} = 11 659 204(7)(5) x 10^{-10} is in good agreement with the…
We present the first measurement of the Michel parameter $\xi^\prime$ in the $\tau^-\to\mu^-\bar{\nu}_\mu\nu_\tau$ decay using the full data sample of $988\,\text{fb}^{-1}$ collected by the Belle detector operating at the KEKB asymmetric…
Recently, the E821 experiment at the Brookhaven National Laboratory announced their latest result of their muon g-2 measurement which is about 2.6-\sigma away from the standard model prediction. Taking this result seriously, we examine the…
We report measurements by the T2K experiment of the parameters $\theta_{23}$ and $\Delta m^2_{32}$ which govern the disappearance of muon neutrinos and antineutrinos in the three-flavor PMNS neutrino oscillation model at T2K's neutrino…
Predictions for the muon decay spectrum are usually derived from the derivative-free Hamiltonian. However, it is not the most general form of the possible interactions. Additional simple terms with derivatives can be introduced. In this…
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…
The distribution of the $K^\pm\to\pi^\pm\pi^+\pi^-$ decays in the Dalitz plot has been measured by the NA48/2 experiment at the CERN SPS with a sample of $4.71\times 10^8$ fully reconstructed events. With the standard Particle Data Group…
We present a determination of the gluon polarisation Delta g/g in the nucleon, based on the longitudinal double-spin asymmetry of DIS events with a pair of large transverse-momentum hadrons in the final state. The data were obtained by the…
The MuLan experiment will measure the lifetime of the positive muon to 1ppm. Within the Standard Model framework, this will permit a determination of the Fermi Constant to 0.5ppm. I present an update on our progress and achievements to…
We test whether or not the tau lepton manifests the same couplings as the mu lepton by investigating the relative decay rates in purely leptonic D+ meson decays. Specifically, we place the first upper limit on the ratio R=Gamma(D+ -> tau+…
The CELSIUS/WASA setup is used to measure the 3pi0 decay of eta mesons produced in pp interactions with beam kinetic energies of 1.36 and 1.45 GeV. The efficiency-corrected Dalitz plot and density distributions for this decay are shown,…
Precision measurements in allowed nuclear beta decays and neutron decay are reviewed and analyzed both within the Standard Model and looking for new physics. The analysis incorporates the most recent experimental and theoretical…
This talk presented the first muon anti-neutrino disappearance analysis using data from the T2K anti-neutrino data taken in 2014 and up to March 12, 2015. The preliminary measured oscillation parameters, using $2.3\times 10^{20}$ protons on…
We generalize the existing analyses of the parity violating muon polarization asymmetry $\Delta_{LR}$ in $K^+\to\pi^+\mu^+\mu^-$ beyond the leading logarithmic approximation. The inclusion of next--to--leading QCD corrections reduces the…
This article reviews the current theoretical and experimental status of the field of muon decay and its potential to search for new physics beyond the Standard Model. The importance of rare muon processes with lepton flavor violation is…
Recently, the ATLAS and CMS Collaborations measured the 125 GeV Higgs boson decay to a pair of muons $h\rightarrow \mu \bar{\mu}$, which reported the signal strength relative to the standard model (SM) prediction is $1.2\pm0.6$ and…
We compute supersymmetric contributions to pion leptonic (\pi_{l2}) decays in the Minimal Supersymmetric Standard Model (MSSM). When R-parity is conserved, the largest contributions to the ratio R_{e/\mu} = \Gamma[ \pi^+ \to e^+…
We have reevaluated the hadronic contribution to the anomalous magnetic moment of the muon (g-2) and to the running of the QED fine structure constant alpha(s) at s=M_Z**2. We incorporated new data from hadronic tau decays, recently…