TY - JOUR
T1 - Measurement of the inclusive and fiducial tt¯tt¯ production cross-sections in the lepton+jets channel in pp collisions at s√=8 TeVs=8 TeV with the ATLAS detector
AU - Bethani, Agni
AU - Connelly, Ian
AU - Cox, Brian
AU - Da Via, Cinzia
AU - Dann, Nicholas
AU - Forti, Alessandra
AU - Lack, David
AU - Loebinger, Frederick
AU - Masik, Jiri
AU - Menary, Stephen
AU - Munoz Sanchez, Francisca
AU - Oh, Alexander
AU - Orgill, Emily
AU - Pater, Joleen
AU - Peters, Yvonne
AU - Pilkington, Andrew
AU - Price, Darren
AU - Qin, Yang
AU - Rawling, Jacob
AU - Roberts, Rhys
AU - Shaw, Savanna
AU - Watts, Stephen
AU - Wilk, Fabian
AU - Wyatt, Terence
AU - The ATLAS Collaboration,
PY - 2018
Y1 - 2018
N2 - The inclusive and fiducial tt¯tt¯ production cross-sections are measured in the lepton+jets channel using 20.2 fb−120.2 fb−1 of proton–proton collision data at a centre-of-mass energy of 8 TeV recorded with the ATLAS detector at the LHC. Major systematic uncertainties due to the modelling of the jet energy scale and b-tagging efficiency are constrained by separating selected events into three disjoint regions. In order to reduce systematic uncertainties in the most important background, the W+\,jetsW+\,jets process is modelled using ZZ + jets events in a data-driven approach. The inclusive tt¯tt¯ cross-section is measured with a precision of 5.7% to be σinc(tt¯)=248.3±0.7(stat.)±13.4(syst.)±4.7(lumi.) pbσinc(tt¯)=248.3±0.7(stat.)±13.4(syst.)±4.7(lumi.) pb , assuming a top-quark mass of 172.5 GeV. The result is in agreement with the Standard Model prediction. The cross-section is also measured in a phase space close to that of the selected data. The fiducial cross-section is σfid(tt¯)=48.8±0.1(stat.)±2.0(syst.)±0.9(lumi.) pbσfid(tt¯)=48.8±0.1(stat.)±2.0(syst.)±0.9(lumi.) pb with a precision of 4.5%.
AB - The inclusive and fiducial tt¯tt¯ production cross-sections are measured in the lepton+jets channel using 20.2 fb−120.2 fb−1 of proton–proton collision data at a centre-of-mass energy of 8 TeV recorded with the ATLAS detector at the LHC. Major systematic uncertainties due to the modelling of the jet energy scale and b-tagging efficiency are constrained by separating selected events into three disjoint regions. In order to reduce systematic uncertainties in the most important background, the W+\,jetsW+\,jets process is modelled using ZZ + jets events in a data-driven approach. The inclusive tt¯tt¯ cross-section is measured with a precision of 5.7% to be σinc(tt¯)=248.3±0.7(stat.)±13.4(syst.)±4.7(lumi.) pbσinc(tt¯)=248.3±0.7(stat.)±13.4(syst.)±4.7(lumi.) pb , assuming a top-quark mass of 172.5 GeV. The result is in agreement with the Standard Model prediction. The cross-section is also measured in a phase space close to that of the selected data. The fiducial cross-section is σfid(tt¯)=48.8±0.1(stat.)±2.0(syst.)±0.9(lumi.) pbσfid(tt¯)=48.8±0.1(stat.)±2.0(syst.)±0.9(lumi.) pb with a precision of 4.5%.
U2 - 10.1140/epjc/s10052-018-5904-z
DO - 10.1140/epjc/s10052-018-5904-z
M3 - Article
SN - 1434-6044
JO - European Physical Journal C. Particles and Fields
JF - European Physical Journal C. Particles and Fields
ER -