Search for a heavy resonance decaying into a Z+jet final state in pp̄ collisions at s=1.96TeV using the D0 detector
Physical Review D - Particles, Fields, Gravitation and Cosmology 74:1 (2006)
Abstract:
We have searched for a heavy resonance decaying into a Z+jet final state in pp̄ collisions at a center of mass energy of 1.96TeV at the Fermilab Tevatron collider using the D0 detector. No indication for such a resonance was found in a data sample corresponding to an integrated luminosity of 370pb-1. We set upper limits on the cross section times branching fraction for heavy resonance production at the 95% C.L. as a function of the resonance mass and width. The limits are interpreted within the framework of a specific model of excited quark production. © 2006 The American Physical Society.Search for new physics in lepton+photon+X events with 305pb-1 of pp̄ collisions at s=1.96 TeV
Physical Review Letters 97:3 (2006)
Abstract:
We present results of a search for anomalous production of events containing a charged lepton (l, either e or μ) and a photon (γ), both with high transverse momentum, accompanied by additional signatures X, including missing transverse energy (ET) and additional leptons and photons. We use the same selection criteria as in a previous CDF search but with a substantially larger data set, 305 pb-1, a pp̄ collision energy of 1.96 TeV, and the CDF II detector. We find 42lγET events versus an expectation of 37.3±5.4 events. We observe 31 γ+X events versus an expectation of 23.0±2.7 events. We find no events similar to the run eeγγET event. © 2006 The American Physical Society.Search for R-parity violating supersymmetry via the L L over(E, ̄) couplings λ121 , λ122 or λ133 in p over(p, ̄) collisions at sqrt(s) = 1.96 TeV
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics 638:5-6 (2006) 441-449
Abstract:
A search for gaugino pair production with a trilepton signature in the framework of R-parity violating supersymmetry via the couplings λ121, λ122, or λ133 is presented. The data, corresponding to an integrated luminosity of L ≈ 360 pb-1, were collected from April 2002 to August 2004 with the D∅ detector at the Fermilab Tevatron Collider, at a center-of-mass energy of sqrt(s) = 1.96 TeV. This analysis considers final states with three charged leptons with the flavor combinations eeℓ, μμℓ, and eeτ (ℓ = e or μ). No evidence for supersymmetry is found and limits at the 95% confidence level are set on the gaugino pair production cross section and lower bounds on the masses of the lightest neutralino and chargino are derived in two supersymmetric models. © 2006 Elsevier B.V. All rights reserved.Direct limits on the oscillation frequency.
Phys Rev Lett 97:2 (2006) 021802
Abstract:
We report results of a study of the B(s)(0) oscillation frequency using a large sample of B(s)(0) semileptonic decays corresponding to approximately 1 fb(-1) of integrated luminosity collected by the D0 experiment at the Fermilab Tevatron Collider in 2002-2006. The amplitude method gives a lower limit on the B(s)(0) oscillation frequency at 14.8 ps(-1) at the 95% C.L. At delta m(s) = 19 ps(-1), the amplitude deviates from the hypothesis A= 0(1) by 2.5 (1.6) standard deviations, corresponding to a two-sided C.L. of 1% (10%). A likelihood scan over the oscillation frequency, delta m(s), gives a most probable value of 19 ps(-1) and a range of 17 < delta m(s) < 21 ps(-1)at the 90% C.L., assuming Gaussian uncertainties. This is the first direct two-sided bound measured by a single experiment. If delta m(s) lies above 22 ps(-1), then the probability that it would produce a likelihood minimum similar to the one observed in the interval 16-22 ps(-1) is (5.0 +/- 0.3)%.Measurement of the Bc+ meson lifetime using the decay mode Bc+ --> J/Psie+nue.
Phys Rev Lett 97:1 (2006) 012002