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Series

2002

Gregory Snow Publications

Articles 1 - 9 of 9

Full-Text Articles in Physics

Search For The Production Of Single Sleptons Through R-Parity Violation In Pp̅ Collisions At √S = 1.8 Tev, V. M. Abazov, Gregory R. Snow, D0 Collaboration Dec 2002

Search For The Production Of Single Sleptons Through R-Parity Violation In Pp̅ Collisions At √S = 1.8 Tev, V. M. Abazov, Gregory R. Snow, D0 Collaboration

Gregory Snow Publications

We report the first search for supersymmetric particles via s-channel production and decay of smuons or muon sneutrinos at hadronic colliders. The data for the two-muon and two-jets final states were collected by the D0 experiment and correspond to an integrated luminosity of 94 ± 5 pb-1. Assuming that R parity is violated via the single coupling λ′211, the number of candidate events is in agreement with expectation from the standard model. Exclusion contours are given in the (m0; m½) and (mΧ̅,mν planes for λ′ …

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Search For Minimal Supergravity In Single-Electron Events With Jets And Large Missing Transverse Energy In Pp̅ Collisions At √S =1.8 Tev, V. M. Abazov, Gregory R. Snow, D0 Collaboration Dec 2002

Search For Minimal Supergravity In Single-Electron Events With Jets And Large Missing Transverse Energy In Pp̅ Collisions At √S =1.8 Tev, V. M. Abazov, Gregory R. Snow, D0 Collaboration

Gregory Snow Publications

We describe a search for evidence of minimal supergravity (MSUGRA) in 92.7 pb-1 of data collected with the DØ detector at the Fermilab Tevatron pp̅ collider at√s =1.8 TeV. Events with a single electron, four or more jets, and large missing transverse energy were used in this search. The major backgrounds are from W +jets, misidentified multijet, tt̅, and WW production. We observe no excess above the expected number of background events in our data. A new limit in terms of MSUGRA model parameters is obtained.

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Search For R-Parity Violating Supersymmetry In Two-Muon And Four-Jet Topologies, V. M. Abazov, Gregory R. Snow, D0 Collaboration Oct 2002

Search For R-Parity Violating Supersymmetry In Two-Muon And Four-Jet Topologies, V. M. Abazov, Gregory R. Snow, D0 Collaboration

Gregory Snow Publications

We present results of a search for R-parity-violating decay of the neutralino Χ̅10, taken as the lightest supersymmetric particle, to a muon and two jets. The decay proceeds through a lepton-number violating coupling λ2jk1 (j =1, 2; k = 1; 2, 3), with R-parity conservation in all other production and decay processes. In the absence of candidate events from 77.5 ± 3.9 pb-1 of data collected by the D0 experiment at the Fermilab Tevatron in pp̅ collisions at√s =1.8 TeV, and with an expected background of 0.18 ± 0.03 …

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Direct Measurement Of The W Boson Decay Width, V. M. Abazov, Gregory R. Snow, D0 Collaboration Aug 2002

Direct Measurement Of The W Boson Decay Width, V. M. Abazov, Gregory R. Snow, D0 Collaboration

Gregory Snow Publications

Based on 85 pb-1 data of pp̅ collisions at √s = 1.8 TeV collected using the DØ detector at Fermilab during the 1994–1995 run of the Tevatron, we present a direct measurement of the total decay width of the W boson ΓW . The width is determined from the transverse mass spectrum in the W→e+ν ℯ decay channel and found to be ΓW=2.23-0.14+0.15 (stat) ±0.10(syst) GeV, consistent with the expectation from the standard model.

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Improved W Boson Mass Measurement With The Dø Detector, V. M. Abazov, Gregory R. Snow, D0 Collaboration Jun 2002

Improved W Boson Mass Measurement With The Dø Detector, V. M. Abazov, Gregory R. Snow, D0 Collaboration

Gregory Snow Publications

We have measured the W boson mass using the DØ detector and a data sample of 82 pb-1 from the Fermilab Tevatron collider. This measurement uses W→eν decays, where the electron is close to a boundary of a central electromagnetic calorimeter module. Such “edge” electrons have not been used in any previous DØ analysis, and represent a 14% increase in the W boson sample size. For these electrons, new response and resolution parameters are determined, and revised backgrounds and underlying event energy flow measurements are made. When the current measurement is combined with previous DØ W boson mass …

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Search For Leptoquark Pairs Decaying Into Νν + Jets In Pp̅ Collisions At √S = 1.8 Tev, V. M. Abazov, Gregory R. Snow, D0 Collaboration May 2002

Search For Leptoquark Pairs Decaying Into Νν + Jets In Pp̅ Collisions At √S = 1.8 Tev, V. M. Abazov, Gregory R. Snow, D0 Collaboration

Gregory Snow Publications

We present the results of a search for leptoquark (LQ) pairs in (85.2 ± 3.7) pb-1 of pp̅ collider data collected by the D0 experiment at the Fermilab Tevatron. We observe no evidence for leptoquark production and set a limit on σ(pp̅→ LQ L̅Q̅→ νν + jets) as a function of the mass of the leptoquark (mLQ). Assuming the decay LQ → νq, we exclude scalar leptoquarks for mLQ< 98 GeV/c2, and vector leptoquarks for mLQ < 200 GeV/c2 and coupling which produces the minimum cross section, at a 95% confidence …

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Search For The Scalar Top Quark In Pp̅ Collisions At √S = 1.8 Tev, V. M. Abazov, Gregory R. Snow, Do Collaboration Apr 2002

Search For The Scalar Top Quark In Pp̅ Collisions At √S = 1.8 Tev, V. M. Abazov, Gregory R. Snow, Do Collaboration

Gregory Snow Publications

We have performed a search for scalar top quark (stop) pair production in the inclusive electronmuon- missing transverse energy final state, using a sample of pp̅ events corresponding to 108.3 pb-1 of data collected with the D0 detector at Fermilab. The search is done in the framework of the minimal supersymmetric standard model assuming that the sneutrino is the lightest supersymmetric particle. For the dominant decays of the lightest stop, t̅→ b χ1+ and t̅→bℓν, no evidence for signal is found. We derive cross-section limits as a function of stop (t̅), …

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Direct Search For Charged Higgs Bosons In Decays Of Top Quarks, V. M. Abazov, Gregory R. Snow, D0 Collaboration Apr 2002

Direct Search For Charged Higgs Bosons In Decays Of Top Quarks, V. M. Abazov, Gregory R. Snow, D0 Collaboration

Gregory Snow Publications

We present a search for charged Higgs bosons in decays of pair-produced top quarks in pp̅ collisions at√s = 1.8 TeV recorded by the D0 detector at the Fermilab Tevatron collider. With no evidence for signal, we exclude most regions of the (MH±, tan β) parameter space where the decay t → H+b has a branching fraction >0.36 and B(H± → τντ is large.

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Subjet Multiplicity Of Gluon And Quark Jets Reconstructed With The K ┴ Algorithm In Pp̅ Collisions, V. M. Abazov, Gregory R. Snow, D0 Collaboration Feb 2002

Subjet Multiplicity Of Gluon And Quark Jets Reconstructed With The K ┴ Algorithm In Pp̅ Collisions, V. M. Abazov, Gregory R. Snow, D0 Collaboration

Gregory Snow Publications

The DØ Collaboration has studied for the first time the properties of hadron-collider jets reconstructed with a successive-combination algorithm based on relative transverse momenta (k ┴) of energy clusters. Using the standard value D=1.0 of the jet-separation parameter in the k ┴ algorithm, we find that the pT of such jets is higher than the ET of matched jets reconstructed with cones of radius R=0.7, by about 5 (8) GeV at pT ≈'90 (240) GeV. To examine internal jet structure, the k ┴ algorithm is applied within D=0.5 jets to resolve any …

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