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CDF Collaboration(Aaltonen, T. et al), & Cabrera, S. (2010). Search for R-Parity Violating Decays of Sneutrinos to e mu, μtau, and e tau Pairs in p(p)over-bar Collisions at root s=1.96 TeV. Phys. Rev. Lett., 105(19), 191801–7pp.
Abstract: We present a search for supersymmetric neutrino (nu) over tilde production using the Tevatron p (p) over bar collision data collected with the CDF II detector and corresponding to an integrated luminosity of 1 fb(-1). We focus on the scenarios predicted by the R-parity violating (RPV) supersymmetric models in which sneutrinos decay to two charged leptons of different flavor. With the data consistent with the standard model expectations, we set upper limits on sigma(p (p) over bar -> (nu) over tilde) BR((nu) over tilde -> e mu, μtau, e tau) and use these results to constrain the RPV couplings as a function of the sneutrino mass.
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MiniBooNE Collaboration(Aguilar-Arevalo, A. A. et al), & Sorel, M. (2010). Measurement of v(mu) and (v)over-bar(mu) induced neutral current single pi(0) production cross sections on mineral oil at E-v similar to O (1 GeV). Phys. Rev. D, 81(1), 013005–14pp.
Abstract: MiniBooNE reports the first absolute cross sections for neutral current single pi(0) production on CH2 induced by neutrino and antineutrino interactions measured from the largest sets of NC pi(0) events collected to date. The principal result consists of differential cross sections measured as functions of pi(0) momentum and pi(0) angle averaged over the neutrino flux at MiniBooNE. We find total cross sections of (4.76 +/- 0.05(stat) +/- 0.76(sys)) X 10(-40) cm(2)/nucleon at a mean energy of < E-v > = 808 MeV and (1.48 +/- 0.05(stat) +/- 0.23(sys)) X 10(-40) cm(2)/nucleon at a mean energy of < E-v > = 664 MeV for v(mu) and (v) over bar (mu) induced production, respectively. In addition, we have included measurements of the neutrino and antineutrino total cross sections for incoherent exclusive NC 1 pi(0) production corrected for the effects of final state interactions to compare to prior results.
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Wu, J. J., Molina, R., Oset, E., & Zou, B. S. (2010). Prediction of Narrow N* and Lambda* Resonances with Hidden Charm above 4 GeV. Phys. Rev. Lett., 105(23), 232001–4pp.
Abstract: The interaction between various charmed mesons and charmed baryons is studied within the framework of the coupled-channel unitary approach with the local hidden gauge formalism. Several meson-baryon dynamically generated narrow N* and Lambda* resonances with hidden charm are predicted with mass above 4 GeV and width smaller than 100 MeV. The predicted new resonances definitely cannot be accommodated by quark models with three constituent quarks and can be looked for in the forthcoming PANDA/FAIR experiments.
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Bodenstein, S., Bordes, J., Dominguez, C. A., Peñarrocha, J., & Schilcher, K. (2010). Charm-quark mass from weighted finite energy QCD sum rules. Phys. Rev. D, 82(11), 114013–5pp.
Abstract: The running charm-quark mass in the scheme is determined from weighted finite energy QCD sum rules involving the vector current correlator. Only the short distance expansion of this correlator is used, together with integration kernels (weights) involving positive powers of s, the squared energy. The optimal kernels are found to be a simple pinched kernel and polynomials of the Legendre type. The former kernel reduces potential duality violations near the real axis in the complex s plane, and the latter allows us to extend the analysis to energy regions beyond the end point of the data. These kernels, together with the high energy expansion of the correlator, weigh the experimental and theoretical information differently from e. g. inverse moments finite energy sum rules. Current, state of the art results for the vector correlator up to four-loop order in perturbative QCD are used in the finite energy sum rules, together with the latest experimental data. The integration in the complex s plane is performed using three different methods: fixed order perturbation theory, contour improved perturbation theory, and a fixed renormalization scale mu. The final result is (m) over bar (c)(3 GeV) = 1008 +/- 26 MeV, in a wide region of stability against changes in the integration radius s(0) in the complex s plane.
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CDF Collaboration(Aaltonen, T. et al), & Cabrera, S. (2010). Search for the supersymmetric partner of the top quark in p(p)over-bar collisions at root s = 1.96 TeV. Phys. Rev. D, 82(9), 092001–16pp.
Abstract: We present a search for the lightest supersymmetric partner of the top quark in proton-antiproton collisions at a center-of-mass energy root s = 1: 96 TeV. This search was conducted within the framework of the R parity conserving minimal supersymmetric extension of the standard model, assuming the stop decays dominantly to a lepton, a sneutrino, and a bottom quark. We searched for events with two oppositely-charged leptons, at least one jet, and missing transverse energy in a data sample corresponding to an integrated luminosity of 1 fb(-1) collected by the Collider Detector at Fermilab experiment. No significant evidence of a stop quark signal was found. Exclusion limits at 95% confidence level in the stop quark versus sneutrino mass plane are set. Stop quark masses up to 180 GeV/c(2) are excluded for sneutrino masses around 45 GeV/c(2), and sneutrino masses up to 116 GeV/c(2) are excluded for stop quark masses around 150 GeV/c(2).
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