Measurements of the jet activity in tt¯ events produced in proton-proton collisions at s=8 TeV are presented, using 20.3 fb−1 of data collected by the ATLAS experiment at the Large Hadron Collider. The events were selected in the dilepton eμ decay channel with two identified b-jets. The numbers of additional jets for various jet transverse momentum (pT) thresholds, and the normalised differential cross-sections as a function of pT for the five highest-pT additional jets, were measured in the jet pseudo-rapidity range |η| < 4.5. The gap fraction, the fraction of events which do not contain an additional jet in a central rapidity region, was measured for several rapidity intervals as a function of the minimum pT of a single jet or the scalar sum of pT of all additional jets. These fractions were also measured in different intervals of the invariant mass of the eμbb¯ system. All measurements were corrected for detector effects, and found to be mostly well-described by predictions from next-to-leading-order and leading-order tt¯ event generators with appropriate parameter choices. The results can be used to further optimise the parameters used in such generators.[Figure not available: see fulltext.] © 2016, The Author(s).
Measurement of jet activity in top quark events using the eμ final state with two b-tagged jets in pp collisions at √s=8 TeV with the ATLAS detector / Aloisio, Alberto; Alviggi, Mariagrazia; Canale, Vincenzo; Della Pietra, Massimo; Merola, Leonardo; Giordano, Raffaele; Conventi, Francesco; Rossi, Elvira; Carlino, Giampaolo; de Asmundis, Riccardo; Di Donato, Camilla; Doria, Aless; Ra, ; Iengo, Paolo; Izzo, Vincenzo; Perrella, Sabrina; Sekhniaidze, Givi; Cirotto, Francesco; Atlas, Collaboration. - In: JOURNAL OF HIGH ENERGY PHYSICS. - ISSN 1029-8479. - 2016:9(2016). [10.1007/JHEP09(2016)074]
Measurement of jet activity in top quark events using the eμ final state with two b-tagged jets in pp collisions at √s=8 TeV with the ATLAS detector
Aloisio, Alberto;Alviggi, MariaGrazia;Canale, Vincenzo;Della Pietra, Massimo;Merola, Leonardo;Giordano, Raffaele;Rossi, Elvira;de Asmundis, Riccardo;Izzo, Vincenzo;Perrella, Sabrina;Cirotto, Francesco;
2016
Abstract
Measurements of the jet activity in tt¯ events produced in proton-proton collisions at s=8 TeV are presented, using 20.3 fb−1 of data collected by the ATLAS experiment at the Large Hadron Collider. The events were selected in the dilepton eμ decay channel with two identified b-jets. The numbers of additional jets for various jet transverse momentum (pT) thresholds, and the normalised differential cross-sections as a function of pT for the five highest-pT additional jets, were measured in the jet pseudo-rapidity range |η| < 4.5. The gap fraction, the fraction of events which do not contain an additional jet in a central rapidity region, was measured for several rapidity intervals as a function of the minimum pT of a single jet or the scalar sum of pT of all additional jets. These fractions were also measured in different intervals of the invariant mass of the eμbb¯ system. All measurements were corrected for detector effects, and found to be mostly well-described by predictions from next-to-leading-order and leading-order tt¯ event generators with appropriate parameter choices. The results can be used to further optimise the parameters used in such generators.[Figure not available: see fulltext.] © 2016, The Author(s).I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
