SwePub
Sök i SwePub databas

  Utökad sökning

Träfflista för sökning "WFRF:(Nugent A. C.) "

Sökning: WFRF:(Nugent A. C.)

Sortera/gruppera träfflistan
   
NumreringReferensOmslagsbildHitta
1.
  • Aad, G., et al. (författare)
  • Charged-particle multiplicities in pp interactions at root s=900 GeV measured with the ATLAS detector at the LHC ATLAS Collaboration
  • 2010
  • Ingår i: Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier. - 0370-2693 .- 1873-2445. ; 688:1, s. 21-42
  • Tidskriftsartikel (refereegranskat)abstract
    • The first measurements from proton-proton collisions recorded with the ATLAS detector at the LHC are presented. Data were collected in December 2009 using a minimum-bias trigger during collisions at a centre-of-mass energy of 900 GeV. The charged-particle multiplicity, its dependence on transverse momentum and pseudorapidity, and the relationship between mean transverse momentum and charged-particle multiplicity are measured for events with at least one charged particle in the kinematic range vertical bar eta vertical bar < 2.5 and p(T) > 500 MeV. The measurements are compared to Monte Carlo models of proton-proton collisions and to results from other experiments at the same centre-of-mass energy. The charged-particle multiplicity per event and unit of pseudorapidity eta = 0 is measured to be 1.333 +/- 0.003(stat.) +/- 0.040(syst.), which is 5-15% higher than the Monte Carlo models predict. 2010 Published by Elsevier B.V.
  •  
2.
  • Aad, G., et al. (författare)
  • Search for heavy vector-like quarks coupling to light quarks in proton-proton collisions at root s=7 TeV with the ATLAS detector
  • 2012
  • Ingår i: Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier. - 0370-2693 .- 1873-2445. ; 712:1-2, s. 22-39
  • Tidskriftsartikel (refereegranskat)abstract
    • This Letter presents a search for singly produced vector-like quarks, Q, coupling to light quarks, q. The search is sensitive to both charged current (CC) and neutral current (NC) processes, pp -> Qq -> Wqq' and pp -> Qq -> Zqq' with a leptonic decay of the vector gauge boson. In 1.04 fb(-1) of data taken in 2011 by the ATLAS experiment at a center-of-mass energy root s = 7 TeV, no evidence of such heavy vector-like quarks is observed above the expected Standard Model background. Limits on the heavy vector-like quark production cross section times branching ratio as a function of mass m(Q) are obtained. For a coupling K-qQ = v/m(Q), where v is the Higgs vacuum expectation value, 95% C.L. lower limits on the mass of a vector-like quark are set at 900 GeV and 760 GeV from CC and NC processes, respectively. (C) 2012 CERN. Published by Elsevier B.V. All rights reserved.
  •  
3.
  • Aad, G., et al. (författare)
  • Measurement of the W -> lv and Z/gamma* -> ll production cross sections in proton-proton collisions at root s=7 TeV with the ATLAS detector
  • 2010
  • Ingår i: Journal of High Energy Physics. - : Springer. - 1029-8479 .- 1126-6708. ; :12
  • Tidskriftsartikel (refereegranskat)abstract
    • First measurements of the W -> lv and Z/gamma* -> ll (l = e; mu) production cross sections in proton-proton collisions at root s = 7 TeV are presented using data recorded by the ATLAS experiment at the LHC. The results are based on 2250 W -> lv and 179 Z/gamma* -> ll candidate events selected from a data set corresponding to an integrated luminosity of approximately 320 nb(-1). The measured total W and Z/gamma*-boson production cross sections times the respective leptonic branching ratios for the combined electron and muon channels are sigma(tot)(W) center dot BR(W -> lv) = 9.96 +/- 0.23(stat) +/- 0.50(syst) +/- 1.10(lumi) nb and sigma(tot)(Z) center dot BR(Z/gamma* -> ll) = 0.82 +/- 0.06 (stat) +/- 0.05 (syst) +/- 0.09 (lumi) nb (within the invariant mass window 66 < m(ll) < 116 GeV). The W/Z cross-section ratio is measured to be 11.7 +/- 0.9(stat) +/- 0.4(syst). In addition, measurements of the W+ and W- production cross sections and of the lepton charge asymmetry are reported. Theoretical predictions based on NNLO QCD calculations are found to agree with the measurements.
  •  
4.
  • Aad, G., et al. (författare)
  • Search for quark contact interactions in dijet angular distributions in pp collisions at root s=7 TeV measured with the ATLAS detector
  • 2011
  • Ingår i: Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier. - 0370-2693 .- 1873-2445. ; 694:4-5, s. 327-345
  • Tidskriftsartikel (refereegranskat)abstract
    • Dijet angular distributions from the first LHC pp collisions at center-of-mass energy root s = 7 TeV have been measured with the ATLAS detector. The dataset used for this analysis represents an integrated luminosity of 3.1 pb(-1). Dijet chi distributions and centrality ratios have been measured up to dijet masses of 2.8 TeV, and found to be in good agreement with Standard Model predictions. Analysis of the chi distributions excludes quark contact interactions with a compositeness scale Lambda below 3.4 TeV, at 95% confidence level, significantly exceeding previous limits. (C) 2010 CERN. Published by Elsevier B.V. All rights reserved.
  •  
5.
  • Aad, G., et al. (författare)
  • Performance of the ATLAS detector using first collision data
  • 2010
  • Ingår i: Journal of High Energy Physics. - : Springer. - 1029-8479 .- 1126-6708. ; 56:9
  • Tidskriftsartikel (refereegranskat)abstract
    • More than half a million minimum-bias events of LHC collision data were collected by the ATLAS experiment in December 2009 at centre-of-mass energies of 0.9 TeV and 2.36 TeV. This paper reports on studies of the initial performance of the ATLAS detector from these data. Comparisons between data and Monte Carlo predictions are shown for distributions of several track- and calorimeter-based quantities. The good performance of the ATLAS detector in these first data gives confidence for successful running at higher energies.
  •  
6.
  • Aad, G., et al. (författare)
  • Search for New Particles in Two-Jet Final States in 7 TeV Proton-Proton Collisions with the ATLAS Detector at the LHC
  • 2010
  • Ingår i: Physical Review Letters. - : American Physical Society. - 1079-7114 .- 0031-9007. ; 105:16
  • Tidskriftsartikel (refereegranskat)abstract
    • A search for new heavy particles manifested as resonances in two-jet final states is presented. The data were produced in 7 TeV proton-proton collisions by the LHC and correspond to an integrated luminosity of 315 nb(-1) collected by the ATLAS detector. No resonances were observed. Upper limits were set on the product of cross section and signal acceptance for excited-quark (q*) production as a function of q* mass. These exclude at the 95% C. L. the q* mass interval 0: 30< m(q)*< 1:26 TeV, extending the reach of previous experiments.
  •  
7.
  • Aad, G., et al. (författare)
  • Measurement of inclusive two-particle angular correlations in pp collisions with the ATLAS detector at the LHC
  • 2012
  • Ingår i: Journal of High Energy Physics. - : Springer. - 1029-8479 .- 1126-6708. ; :5
  • Tidskriftsartikel (refereegranskat)abstract
    • We present a measurement of two-particle angular correlations in proton-proton collisions at root s = 900 GeV and 7 TeV. The collision events were collected during 2009 and 2010 with the ATLAS detector at the Large Hadron Collider using a single-arm minimum bias trigger. Correlations are measured for charged particles produced in the kinematic range of transverse momentum p(T) > 100 MeV and pseudorapidity vertical bar eta vertical bar < 2.5. A complex structure in pseudorapidity and azimuth is observed at both collision energies. Results are compared to PYTHIA 8 and HERWIG++ as well as to the AMBT2B, DW and Perugia 2011 tunes of PYTHIA 6. The data are not satisfactorily described by any of these models.
  •  
8.
  • Aad, G., et al. (författare)
  • Jet mass and substructure of inclusive jets in root s=7 TeV pp collisions with the ATLAS experiment
  • 2012
  • Ingår i: Journal of High Energy Physics. - : Springer. - 1029-8479 .- 1126-6708. ; :5
  • Tidskriftsartikel (refereegranskat)abstract
    • Recent studies have highlighted the potential of jet substructure techniques to identify the hadronic decays of boosted heavy particles. These studies all rely upon the assumption that the internal substructure of jets generated by QCD radiation is well understood. In this article, this assumption is tested on an inclusive sample of jets recorded with the ATLAS detector in 2010, which corresponds to 35 pb(-1) of pp collisions delivered by the LHC at root s = 7 TeV. In a subsample of events with single pp collisions, measurements corrected for detector efficiency and resolution are presented with full systematic uncertainties. Jet invariant mass, k(t) splitting scales and N-subjettiness variables are presented for anti-k(t) R = 1.0 jets and Cambridge-Aachen R = 1.2 jets. Jet invariant-mass spectra for Cambridge-Aachen R = 1.2 jets after a splitting and filtering procedure are also presented. Leading-order parton-shower Monte Carlo predictions for these variables are found to be broadly in agreement with data. The dependence of mean jet mass on additional pp interactions is also explored.
  •  
9.
  • Aad, G., et al. (författare)
  • Search for same-sign top-quark production and fourth-generation down-type quarks in pp collisions at root s=7 TeV with the ATLAS detector
  • 2012
  • Ingår i: Journal of High Energy Physics. - : Springer. - 1029-8479 .- 1126-6708. ; :4
  • Tidskriftsartikel (refereegranskat)abstract
    • A search is preseritecl for same-sign top-quark production and down-type heavy quarks of charge -1/3 in events with two isolated leptons (c or mu) that have the same electric charge, at least two jets and large missing transverse momentum. The data are selected from pp collisions at root s = 7 TeV recorded by the ATLAS detector and correspond to an integrated luminosity of 1.04 fb(-1). The observed data are consistent with expectations from Standard Model processes. Upper limits are set at 95% confidence level on the cross section of new sources of same-sign top-quark pair production of 1.4-2.0 pb depending on the assumed mediator mass. Upper limits are also set on the pair-production cross-section for new heavy down-type quarks; a lower limit of 450 GeV is set at 95% confidence level on the mass of heavy down-type quarks under the assumption that they decay 100% of the time to Wt.
  •  
10.
  • Aad, G., et al. (författare)
  • Search for pair production of first or second generation leptoquarks in proton-proton collisions at root s=7 TeV using the ATLAS detector at the LHC
  • 2011
  • Ingår i: Physical Review D (Particles, Fields, Gravitation and Cosmology). - : American Physical Society. - 1550-2368 .- 1550-7998. ; 83:11
  • Tidskriftsartikel (refereegranskat)abstract
    • This paper describes searches for the pair production of first or second generation scalar leptoquarks using 35 pb(-1) of proton-proton collision data recorded by the ATLAS detector at root s = 7 TeV. Leptoquarks are searched in events with two oppositely-charged muons or electrons and at least two jets, and in events with one muon or electron, missing transverse momentum and at least two jets. After event selection, the observed yields are consistent with the predicted backgrounds. Leptoquark production is excluded at the 95% CL for masses M-LQ < 376 (319) GeV and M-LQ < 422 (362) GeV for first and second generation scalar leptoquarks, respectively, when assuming the branching fraction of a leptoquark to a charged lepton is equal to 1.0 (0.5).
  •  
Skapa referenser, mejla, bekava och länka
Typ av publikation
tidskriftsartikel (304)
konferensbidrag (3)
rapport (2)
forskningsöversikt (1)
Typ av innehåll
refereegranskat (308)
övrigt vetenskapligt (2)
Författare/redaktör
Aad, G (263)
Zwalinski, L. (245)
Lund-Jensen, B. (224)
Kastanas, A. (224)
Abi, B. (224)
Abramowicz, H. (224)
visa fler...
Adelman, J. (224)
Adye, T. (224)
Ahlen, S. P. (224)
Akimoto, G. (224)
Akimov, A. V. (224)
Aleksa, M. (224)
Alexandre, G. (224)
Allport, P. P. (224)
Amelung, C. (224)
Anastopoulos, C. (224)
Anduaga, X. S. (224)
Antonaki, A. (224)
Antonelli, M. (224)
Arai, Y. (224)
Arguin, J. -F. (224)
Arnaez, O. (224)
Asquith, L. (224)
Assamagan, K. (224)
Azuma, Y. (224)
Baak, M. A. (224)
Bachacou, H. (224)
Bachas, K. (224)
Backes, M. (224)
Baker, O. K. (224)
Banas, E. (224)
Barberio, E. L. (224)
Barbero, M. (224)
Barillari, T. (224)
Barisonzi, M. (224)
Barklow, T. (224)
Barlow, N. (224)
Barnett, B. M. (224)
Bates, R. L. (224)
Bauer, F. (224)
Bawa, H. S. (224)
Beau, T. (224)
Beck, H. P. (224)
Beckingham, M. (224)
Belanger-Champagne, ... (224)
Bella, G. (224)
Beltramello, O. (224)
Benary, O. (224)
Benekos, N. (224)
Benhammou, Y. (224)
visa färre...
Lärosäte
Lunds universitet (225)
Kungliga Tekniska Högskolan (212)
Stockholms universitet (66)
Uppsala universitet (14)
Karolinska Institutet (10)
Göteborgs universitet (5)
visa fler...
Umeå universitet (5)
Luleå tekniska universitet (5)
Chalmers tekniska högskola (2)
Linköpings universitet (1)
Södertörns högskola (1)
Linnéuniversitetet (1)
Karlstads universitet (1)
visa färre...
Språk
Engelska (310)
Forskningsämne (UKÄ/SCB)
Naturvetenskap (288)
Medicin och hälsovetenskap (12)
Samhällsvetenskap (4)
Teknik (2)

År

 
pil uppåt Stäng

Kopiera och spara länken för att återkomma till aktuell vy