Search for neutral, long-lived particles decaying into two muons in pp̄ collisions at s=1.96TeV
Physical Review Letters 97:16 (2006)
Abstract:
We present a search for a neutral particle, pair produced in pp̄ collisions at s=1.96TeV, which decays into two muons and lives long enough to travel at least 5 cm before decaying. The analysis uses 380pb-1 of data recorded with the D0 detector. The background is estimated to be about one event. No candidates are observed, and limits are set on the pair-production cross section times branching fraction into dimuons + X for such particles. For a mass of 10 GeV and lifetime of 4×10-11s, we exclude values greater than 0.14 pb (95 C.L.). These results are used to limit the interpretation of NuTeV's excess of dimuon events. © 2006 The American Physical Society.Search for the standard model Higgs Boson in the pp ZH bb channel
Physical Review Letters 97:16 (2006)
Abstract:
We report a search for the standard model (SM) Higgs boson based on data collected by the D0 experiment at the Fermilab Tevatron Collider, corresponding to an integrated luminosity of 260pb-1. We study events with missing transverse energy and two acoplanar b jets, which provide sensitivity to the ZH production cross section in the νν̄bb̄ channel, and to WH production when the lepton from the W→ ν decay is undetected. The data are consistent with the SM background expectation, and we set 95% C.L. upper limits on σ(pp̄→ZH/WH)×B(H→bb̄) from 3.4/8.3 to 2.5/6.3pb, for Higgs-boson masses between 105 and 135 GeV. © 2006 The American Physical Society.Search for pair production of scalar bottom quarks in pp collisions at square root of s = 1.96 TeV.
Phys Rev Lett 97:17 (2006) 171806
Abstract:
A search for direct production of scalar bottom quarks (b) is performed with 310 pb(-1) of data collected by the D0 experiment in pp collisions at square root s = 1.96 TeV at the Fermilab Tevatron Collider. The topology analyzed consists of two b jets and an imbalance in transverse momentum due to undetected neutralinos (chi(1)0), with chi(1)0 assumed to be the lightest supersymmetric particle. We find the data consistent with standard model expectations, and set a 95% C.L. exclusion domain in the (m(b), m(chi(1)0)) mass plane, improving significantly upon the results from run I of the Tevatron.Search for W′ boson production in the W′ → t over(b, ̄) decay channel
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics 641:6 (2006) 423-431
Abstract:
We present a search for the production of a new heavy gauge boson W′ that decays to a top quark and a bottom quark. We have analyzed 230 pb-1 of data collected with the DØ detector at the Fermilab Tevatron collider at a center-of-mass energy of 1.96 TeV. No significant excess of events above the standard model expectation is found in any region of the final state invariant mass distribution. We set upper limits on the production cross section of W′ bosons times branching ratio to top quarks at the 95% confidence level for several different W′ boson masses. We exclude masses between 200 and 610 GeV for a W′ boson with standard-model-like couplings, between 200 and 630 GeV for a W′ boson with right-handed couplings that is allowed to decay to both leptons and quarks, and between 200 and 670 GeV for a W′ boson with right-handed couplings that is only allowed to decay to quarks. © 2006 Elsevier B.V. All rights reserved.Search for particles decaying into a Z boson and a photon in p over(p, ̄) collisions at sqrt(s) = 1.96 TeV
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics 641:6 (2006) 415-422