Updated search for the flavor-changing neutral-current decay D0âÎŒâ+ÎŒâ- in ppÌ collisions at âs=1.96 TeV
Physical Review D - Particles, Fields, Gravitation and Cosmology 82:9 (2010)
Abstract:
We report on a search for the flavor-changing neutral-current decay D0âÎŒâ+ÎŒâ- in ppÌ collisions at âs=1.96TeV using 360pbâ-1 of integrated luminosity collected by the CDF II detector at the Fermilab Tevatron collider. A displaced vertex trigger selects long-lived D0 candidates in the ÎŒâ+ÎŒâ-, Ïâ+Ïâ-, and Kâ-Ïâ+ decay modes. We use the Cabibbo-favored D0âKâ- Ïâ+ channel to optimize the selection criteria in an unbiased manner, and the kinematically similar D0âÏâ+Ïâ- channel for normalization. We set an upper limit on the branching fraction B(D0âÎŒâ+ÎŒâ-)<2.1Ă10â-7(3.0Ă10â-7) at the 90% (95%) confidence level. © 2010 The American Physical Society.Search for R-parity violating decays of sneutrinos to eÎŒ, ÎŒÏ, and eÏ pairs in pp collisions at square root s = 1.96 TeV.
Phys Rev Lett 105:19 (2010) 191801
Abstract:
We present a search for supersymmetric neutrino Μ production using the Tevatron pp 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 Ï(ppâΜ)ĂBR(ΜâeÎŒ,ÎŒÏ,eÏ) and use these results to constrain the RPV couplings as a function of the sneutrino mass.Search for the supersymmetric partner of the top quark in ppÌ collisions at âs=1.96TeV
Physical Review D - Particles, Fields, Gravitation and Cosmology 82:9 (2010)
Abstract:
We present a search for the lightest supersymmetric partner of the top quark in proton-antiproton collisions at a center-of-mass energy âs=1.96TeV. 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 1fbâ-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 180GeV/c2 are excluded for sneutrino masses around 45GeV/c2, and sneutrino masses up to 116GeV/c2 are excluded for stop quark masses around 150GeV/c2. © 2010 The American Physical Society.Search for anomalous production of events with two photons and additional energetic objects at CDF
Physical Review D Particles Fields Gravitation and Cosmology 82:5 (2010)
Abstract:
We present results of a search for anomalous production of two photons together with an electron, muon, Ï lepton, missing transverse energy, or jets using ppÌ collision data from 1.1-2.0fb-1 of integrated luminosity collected by the Collider Detector at Fermilab (CDF). The event yields and kinematic distributions are examined for signs of new physics without favoring a specific model of new physics. The results are consistent with the standard model expectations. The search employs several new analysis techniques that significantly reduce instrumental backgrounds in channels with an electron and missing transverse energy. © 2010 The American Physical Society.Search for new physics with a dijet plus missing E(T) signature in pp collisions at âs=1.96ââTeV.
Phys Rev Lett 105:13 (2010) 131801