dc.contributor.author | Buanes, Trygve | eng |
dc.contributor.author | Burgess, Thomas | eng |
dc.contributor.author | Eigen, Gerald | eng |
dc.contributor.author | Kastanas, Alex | eng |
dc.contributor.author | Liebig, Wolfgang | eng |
dc.contributor.author | Lipniacka, Anna | eng |
dc.contributor.author | Rosendahl, Peter Lundgaard | eng |
dc.contributor.author | Sandaker, Heidi | eng |
dc.contributor.author | Sjursen, Therese B. | eng |
dc.contributor.author | Stugu, Bjarne | eng |
dc.contributor.author | Tonoyan, Arshak | eng |
dc.contributor.author | Ugland, Maren | eng |
dc.contributor.author | Bugge, Lars | eng |
dc.contributor.author | Buran, Torleiv | eng |
dc.contributor.author | Cameron, David Gordon | eng |
dc.contributor.author | Czyczula, Zofia | eng |
dc.contributor.author | Gjelsten, Børge Kile | eng |
dc.contributor.author | Gramstad, Eirik | eng |
dc.contributor.author | Lund, Esben | eng |
dc.contributor.author | Ould-Saada, Farid | eng |
dc.contributor.author | Pajchel, Katarina | eng |
dc.contributor.author | Pedersen, Maiken | eng |
dc.contributor.author | Pylypchenko, Yuriy | eng |
dc.contributor.author | Read, Alexander Lincoln | eng |
dc.contributor.author | Røhne, Ole Myren | eng |
dc.contributor.author | Smestad, Lillian | eng |
dc.contributor.author | Stapnes, Steinar | eng |
dc.contributor.author | Strandlie, Are | eng |
dc.contributor.author | Aad, Georges | eng |
dc.contributor.author | Abajyan, Tatevik | eng |
dc.contributor.author | Abbott, Brad | eng |
dc.contributor.author | Abdallah, Jalal | eng |
dc.contributor.author | Abdel Khalek, Samah | eng |
dc.contributor.author | Abdinov, Ovsat Bahram oglu | eng |
dc.contributor.author | Aben, Rosemarie | eng |
dc.contributor.author | Abi, Babak | eng |
dc.contributor.author | Abolins, Maris | eng |
dc.contributor.author | AbouZeid, Hass | eng |
dc.contributor.author | Abramowicz, Halina | eng |
dc.contributor.author | Abreu, Henso | eng |
dc.contributor.author | Acerbi, Emilio | eng |
dc.contributor.author | Adamczyk, Leszek | eng |
dc.contributor.author | Adams, David | eng |
dc.contributor.author | Addy, Tetteh N. | eng |
dc.contributor.author | Adelman, Jareed | eng |
dc.contributor.author | Adomeit, Stefanie | eng |
dc.contributor.author | Adye, Tim | eng |
dc.contributor.author | Aefsky, Scott Alan | eng |
dc.contributor.author | Agatonovic-Jovin, Tatjana | eng |
dc.contributor.author | Aguilar Saavedra, Juan Antonio | eng |
dc.contributor.author | Aharrouche, Mohamed | eng |
dc.contributor.author | ATLAS, Collaboration | eng |
dc.date.accessioned | 2015-05-15T11:15:34Z | |
dc.date.available | 2015-05-15T11:15:34Z | |
dc.date.issued | 2014-04-21 | eng |
dc.identifier.issn | 0556-2821 | en_US |
dc.identifier.uri | https://hdl.handle.net/1956/9881 | |
dc.description.abstract | Using a sample of dilepton top-quark pair (tt¯) candidate events, a study is performed of the production of top-quark pairs together with heavy-flavor (HF) quarks, the sum of tt¯+b+X and tt¯+c+X, collectively referred to as tt¯ + HF. The data set used corresponds to an integrated luminosity of 4.7 fb−1 of proton-proton collisions at a center-of-mass energy of 7 TeV recorded by the ATLAS detector at the CERN Large Hadron Collider. The presence of additional HF (b or c) quarks in the tt¯ sample is inferred by looking for events with at least three b-tagged jets, where two are attributed to the b quarks from the tt¯ decays and the third to additional HF production. The dominant background to tt¯ + HF in this sample is tt¯+jet events in which a light-flavor jet is misidentified as a heavy-flavor jet. To determine the heavy- and light-flavor content of the additional b-tagged jets, a fit to the vertex mass distribution of b-tagged jets in the sample is performed. The result of the fit shows that 79 ± 14 (stat) ± 22 (syst) of the 105 selected extra b-tagged jets originate from HF quarks, 3 standard deviations away from the hypothesis of zero tt¯ + HF production. The result for extra HF production is quoted as a ratio (RHF) of the cross section for tt¯ + HF production to the cross section for tt¯ production with at least one additional jet. Both cross sections are measured in a fiducial kinematic region within the ATLAS acceptance. RHF is measured to be [6.2±1.1(stat)±1.8(syst)]% for jets with pT>25 GeV and |η|<2.5, in agreement with the expectations from Monte Carlo generators. | en_US |
dc.language.iso | eng | eng |
dc.publisher | American Physical Society | en_US |
dc.rights | Attribution CC BY | eng |
dc.rights.uri | http://creativecommons.org/licenses/by/3.0/ | eng |
dc.title | Study of heavy-flavor quarks produced in association with top-quark pairs at √s =7 TeV using the ATLAS detector | en_US |
dc.type | Peer reviewed | |
dc.type | Journal article | |
dc.date.updated | 2015-04-09T06:44:45Z | en_US |
dc.description.version | publishedVersion | en_US |
dc.rights.holder | Copyright 2014 CERN, for the ATLAS Collaboration | en_US |
dc.source.articlenumber | 72012 | |
dc.identifier.doi | https://doi.org/10.1103/physrevd.89.072012 | |
dc.identifier.cristin | 1149196 | |
dc.source.journal | Physical Review D | |
dc.source.40 | 89 | |
dc.source.14 | 7 | |
dc.subject.nsi | VDP::Mathematics and natural scienses: 400::Physics: 430::Nuclear and elementary particle physics: 431 | en_US |
dc.subject.nsi | VDP::Matematikk og naturvitenskap: 400::Fysikk: 430::Kjerne- og elementærpartikkelfysikk: 431 | nob |