M . Ronquest

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E. Abouzaid, M. Arenton, A. R. Barker,* M. Barrio, L. Bellantoni, E. Blucher, G. J. Bock, C. Bown, E. Cheu, R. Coleman, M.D. Corcoran, B. Cox, A. R. Erwin, C. O. Escobar, A. Glazov, A. Golossanov, R.A. Gomes, P. Gouffon, J. Graham, J. Hamm, Y. B. Hsiung, D.A. Jensen, R. Kessler, K. Kotera, J. LaDue, A. Ledovskoy, P. L. McBride, E. Monnier, H. Nguyen, R.(More)
The KTeV E799 experiment has conducted a search for the rare decays, K(L)→π(0)π(0)μ(+)μ(-) and K(L)→π(0)π(0)X(0)→π(0)π(0)μ(+)μ(-), where the X(0) is a possible new neutral boson that was reported by the HyperCP experiment with a mass of (214.3 ± 0.5) MeV/c(2). We find no evidence for either decay. We obtain upper limits of(More)
The KTeV/E799 experiment at Fermilab has searched for the rare kaon decay K(L)-->pi(0)e(+)e(-). This mode is expected to have a significant CP violating component. The measurement of its branching ratio could support the standard model or could indicate the existence of new physics. This Letter reports new results from the 1999-2000 data set. One event is(More)
E. Abouzaid, M. Arenton, A.R. Barker, ∗ L. Bellantoni, E. Blucher, G.J. Bock, E. Cheu, R. Coleman, M.D. Corcoran, B. Cox, A.R. Erwin, C.O. Escobar, A. Glazov, A. Golossanov, R.A. Gomes, P. Gouffon, Y.B. Hsiung, D.A. Jensen, R. Kessler, K. Kotera, A. Ledovskoy, P.L. McBride, E. Monnier, † H. Nguyen, R. Niclasen, D.G. Phillips II, E.J. Ramberg, R.E. Ray, M.(More)
We present a determination of the Cabibbo-Kobayashi-Maskawa parameter |V(us)| based on new measurements of the six largest K(L) branching fractions and semileptonic form factors by the KTeV (E832) experiment at Fermilab. We find |V(us)|=0.2252+/-0.0008(KTeV)+/-0.0021(ext), where the errors are from KTeV measurements and from external sources. We also use(More)
E. Abouzaid, A. Alavi-Harati, T. Alexopoulos, M. Arenton, A.R. Barker, L. Bellantoni, A. Bellavance, E. Blucher, G.J. Bock, S. Bright, E. Cheu, R. Coleman, M.D. Corcoran, B. Cox, A.R. Erwin, C.O. Escobar, R. Ford, A. Glazov, A. Golossanov, R.A. Gomes, P. Gouffon, K. Hanagaki, Y.B. Hsiung, H. Huang, D.A. Jensen, R. Kessler, K. Kotera, A. Ledovskoy, P.L.(More)
This Letter is the first report of the K{L}-->pi{+/-}e{-/+}nue{+}e{-} decay. Based on 19 208+/-144 events, we determine the branching fraction, B(K{L}-->pi{+/-}e{-/+}nue{+}e{-}M_{e{+}e{-}}>5 MeV/c{2},E{e{+}e{-}}{*}>30 MeV)=(1.285+/-0.041)x10{-5}, and Gamma(K{e3ee}M{e{+}e{-}}>5 MeV/c{2})/Gamma(K{e3})=[4.57+/-0.04(stat)+/-0.14(syst)]x10{-5}. This ratio agrees(More)
The xi0 muon semileptonic decay has been observed for the first time with nine identified events using the KTeV beam line and detector at Fermilab. The decay is normalized to the xi0 beta decay mode and yields a value for the ratio of decay rates gamma(xi0 --> sigma+ mu- nu(mu))/gamma(xi0 --> sigma+ e- nu(e)) of [1.8(-0.5)(+0.7)(stat) +/- 0.2(syst)] x(More)