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Full-Text Articles in Physics
Ratio Of Isolated Photon Cross Sections In Pp̅ Collisions At √S = 630 And 1800 Gev, V. M. Abazov, Gregory R. Snow, D0 Collaboration
Ratio Of Isolated Photon Cross Sections In Pp̅ Collisions At √S = 630 And 1800 Gev, V. M. Abazov, Gregory R. Snow, D0 Collaboration
Gregory Snow Publications
The inclusive cross section for production of isolated photons has been measured in pp̅ collisions at √s = 630 GeV with the D0 detector at the Fermilab Tevatron Collider. The photons span a transverse energy (ET) range from 7–49 GeV and have pseudorapidity∣η∣ < 2.5. This measurement is combined with the previous D0 result at √s = 1800 GeV to form a ratio of the cross sections. Comparison of next-to-leading-order QCD with the measured cross section at 630 GeV and the ratio of cross sections show satisfactory agreement in most of the ET range.
Search For New Physics Using Quaero: A General Interface To D0 Event Data, V. M. Abazov, Gregory R. Snow, D0 Collaboration
Search For New Physics Using Quaero: A General Interface To D0 Event Data, V. M. Abazov, Gregory R. Snow, D0 Collaboration
Gregory Snow Publications
We describe QUAERO, a method that (i) enables the automatic optimization of searches for physics beyond the standard model, and (ii) provides a mechanism for making high energy collider data generally available. We apply QUAERO to searches for standard model WW, ZZ , and tt̅ production, to searches for these objects produced through a new heavy resonance, and to the first direct search for W′→ WZ. Through this interface, we make three data sets collected by the D0 experiment at √s =1.8 TeV publicly available.
Search For First-Generation Scalar And Vector Leptoquarks, V. M. Abazov, Gregory R. Snow, D0 Collaboration
Search For First-Generation Scalar And Vector Leptoquarks, V. M. Abazov, Gregory R. Snow, D0 Collaboration
Gregory Snow Publications
We describe a search for the pair production of first-generation scalar and vector leptoquarks in the ee j j and eν jj channels by the DO. Collaboration. The data are from the 1992–1996 pp̅ run at √s =1.8 TeV at the Fermilab Tevatron collider. We find no evidence for leptoquark production; in addition, no kinematically interesting events are observed using relaxed selection criteria. The results from the ee j j and eν jj channels are combined with those from a previous DO. analysis of the νν jj channel to obtain 95% confidence level (C.L.) upper limits on the leptoquark …
Search For Heavy Particles Decaying Into Electron-Positron Pairs In Pp̅ Collisions, V. M. Abazov, Gregory R. Snow, D0 Collaboration
Search For Heavy Particles Decaying Into Electron-Positron Pairs In Pp̅ Collisions, V. M. Abazov, Gregory R. Snow, D0 Collaboration
Gregory Snow Publications
We present results of searches for technirho (ρT), techniomega (ωT), and Z ′ particles, using the decay channels ρT, ωT, Z ′ → ℯ+ℯ-. The search is based on 124.8 pb-1 of data collected by the D0 detector at the Fermilab Tevatron during 1992–1996. In the absence of a signal, we set 95% C.L. upper limits on the cross sections for the processes pp̅ → ρT, ωT, Z ′ → ℯ+ℯ- as a function of the mass of the decaying …
High-PT Jets In Pp̅ Collisions At √S =630 And 1800 Gev, B. Abbott, Gregory R. Snow, D0 Collaboration
High-PT Jets In Pp̅ Collisions At √S =630 And 1800 Gev, B. Abbott, Gregory R. Snow, D0 Collaboration
Gregory Snow Publications
Results are presented from analyses of jet data produced in pp̅ collisions at √s =630 and 1800 GeV collected with the DØ detector during the 1994–1995 Fermilab Tevatron Collider run. We discuss the details of detector calibration, and jet selection criteria in measurements of various jet production cross sections at √s = 630 and 1800 GeV. The inclusive jet cross sections, the dijet mass spectrum, the dijet angular distributions, and the ratio of inclusive jet cross sections at√s =630 and 1800 GeV are compared to next-to-leading order QCD predictions. The order αs3 calculations are in …
Quasi-Model-Independent Search For New Physics At Large Transverse Momentum, V. M. Abazov, Gregory R. Snow, D0 Collaboration
Quasi-Model-Independent Search For New Physics At Large Transverse Momentum, V. M. Abazov, Gregory R. Snow, D0 Collaboration
Gregory Snow Publications
We apply a quasi-model-independent strategy (“SLEUTH”) to search for new high pT physics in ≈ 100 pb-1 of pp̅ collisions at √s = 1.8 TeV collected by the DØ experiment during 1992–1996 at the Fermilab Tevatron. Over 32 eμX, W+jets-like, Z1jets-like, and (l/γ)(l/γ)(l/γ)X exclusive final states are systematically analyzed for hints of physics beyond the standard model. Simultaneous sensitivity to a variety of models predicting new phenomena at the electroweak scale is demonstrated by testing the method on a particular signature in each set of final states. No evidence of new high pT …
Quasi-Model-Independent Search For New High PT Physics At D0, B. Abbott, Gregory R. Snow, D0 Collaboration
Quasi-Model-Independent Search For New High PT Physics At D0, B. Abbott, Gregory R. Snow, D0 Collaboration
Gregory Snow Publications
We apply a quasi-model-independent strategy (“Sleuth”) to search for new high pT physics in ≈100 pb-1 of pp̅ collisions at √s = 1.8 TeV collected by the D0 experiment during 1992–1996 at the Fermilab Tevatron. We systematically analyze many exclusive final states and demonstrate sensitivity to a variety of models predicting new phenomena at the electroweak scale. No evidence of new high pT physics is observed.
Search For Dilepton Signatures From Minimal Low-Energy Supergravity In Pp̅ Collisions At √S = 1.8 Tev, B. Abbott, Gregory R. Snow, D0 Collaboration
Search For Dilepton Signatures From Minimal Low-Energy Supergravity In Pp̅ Collisions At √S = 1.8 Tev, B. Abbott, Gregory R. Snow, D0 Collaboration
Gregory Snow Publications
We report on a search for supersymmetry using the DØ detector. The 1994–1996 data sample of √s =1.8 TeV pp̅ collisions was analyzed for events containing two leptons (e or μ), two or more jets, and missing transverse energy. Assuming the minimal supergravity model, with A0=0 and μ < 0, various thresholds were employed to optimize the search. No events were found beyond expectation from the background. We set a lower limit at the 95% C.L. of 255 GeV/c2 for equal mass squarks and gluinos for tan β =2, and present exclusion contours in the (m0 , m1/2) plane for tan β =2–6.
Ratio Of Jet Cross Sections At √S = 630 Gev And 1800 Gev, B. Abbott, Gregory R. Snow, D0 Collaboration
Ratio Of Jet Cross Sections At √S = 630 Gev And 1800 Gev, B. Abbott, Gregory R. Snow, D0 Collaboration
Gregory Snow Publications
The D0 Collaboration has measured the inclusive jet cross section in p̅p collisions at √s = 630 GeV. The results for pseudorapidities ∣η∣ < 0.5 are combined with our previous results at √s =1800 GeV to form a ratio of cross sections with smaller uncertainties than either individual measurement. Next-to-leading-order QCD predictions show excellent agreement with the measurement at 630 GeV; agreement is also satisfactory for the ratio. Specifically, despite a 10% to 15% difference in the absolute magnitude, the dependence of the ratio on jet transverse momentum is very similar for data and theory.
Ratios Of Multijet Cross Sections In Pp̅ Collisions At √S = 1.8 Tev, B. Abbott, Gregory R. Snow, D0 Collaboration
Ratios Of Multijet Cross Sections In Pp̅ Collisions At √S = 1.8 Tev, B. Abbott, Gregory R. Snow, D0 Collaboration
Gregory Snow Publications
We report on a study of the ratio of inclusive three-jet to inclusive two-jet production cross sections as a function of total transverse energy in pp̅ collisions at a center-of-mass energy√s = 1.8 TeV, using data collected with the D0 detector during the 1992–1993 run of the Fermilab Tevatron Collider. The measurements are used to deduce preferred renormalization scales in perturbative O(αs3) QCD calculations in modeling soft-jet emission.
Measurement Of The Angular Distribution Of Electrons From W→Eν Decays Observed In Pp̅ Collisions At √S =1.8 Tev, B. Abbott, Gregory R. Snow, D0 Collaboration
Measurement Of The Angular Distribution Of Electrons From W→Eν Decays Observed In Pp̅ Collisions At √S =1.8 Tev, B. Abbott, Gregory R. Snow, D0 Collaboration
Gregory Snow Publications
We present the first measurement of the electron angular distribution parameter α2 in W→eν events produced in proton-antiproton collisions as a function of the W boson transverse momentum. Our analysis is based on data collected using the DØ detector during the 1994–1995 Fermilab Tevatron run. We compare our results with next-to-leading order perturbative QCD, which predicts an angular distribution of (1 ± α1cos θ*+ α2 cos2 θ*), where θ* is the polar angle of the electron in the Collins-Soper frame. In the presence of QCD corrections, the parameters a1 and a2 become functions of …
Inclusive Jet Production In Pp̅ Collisions, B. Abbott
Inclusive Jet Production In Pp̅ Collisions, B. Abbott
Gregory Snow Publications
We report a new measurement of the pseudorapidity (η) and transverse-energy (ET) dependence of the inclusive jet production cross section in pp̅ collisions at √s = TeV using 95 pb-1 of data collected with the D0 detector at the Fermilab Tevatron. The differential cross section d2σ/(dErdη) is presented up to |η| = 3, significantly extending previous measurements. The results are in good overall agreement with next-to-leading order predictions from QCD and indicate a preference for certain parton distribution functions.
Search For Large Extra Dimensions In Dielectron And Diphoton Production, B. Abbott, Gregory R. Snow, D0 Collaboration
Search For Large Extra Dimensions In Dielectron And Diphoton Production, B. Abbott, Gregory R. Snow, D0 Collaboration
Gregory Snow Publications
We report a search for effects of large extra spatial dimensions in pp̅ collisions at a center-of-mass energy of 1.8 TeV with the D0 detector, using events containing a pair of electrons or photons. The data are in good agreement with the expected background and do not exhibit evidence for large extra dimensions. We set the most restrictive lower limits to date, at the 95% C.L. on the effective Planck scale between 1.0 and 1.4 TeV for several formalisms and numbers of extra dimensions.
Search For Electroweak Production Of Single Top Quarks In Pp̅ Collisions, B. Abbott
Search For Electroweak Production Of Single Top Quarks In Pp̅ Collisions, B. Abbott
Gregory Snow Publications
We present a search for electroweak production of single top quarks in the electron+jets and muon+jets decay channels. The measurements use ≈90 pb-1 of data from Run 1 of the Fermilab Tevatron collider, collected at 1.8 TeV with the D Ø detector between 1992 and 1995. We use events that include a tagging muon, implying the presence of a b jet, to set an upper limit at the 95% confidence level on the cross section for the s-channel process pp̅→tb+X of 39 pb. The upper limit for the t-channel processpp̅→tqb+X …