Measurement of the inclusive and fiducial tt¯ production cross-sections in the lepton+jets channel in pp collisions at √s=8 TeV with the ATLAS detector

0500332 - FZÚ 2019 RIV DE eng J - Journal Article
Aaboud, M. - Aad, G. - Abbott, B. - Chudoba, Jiří - Hejbal, Jiří - Hladík, Ondřej - Jakoubek, Tomáš - Kepka, Oldřich - Kroll, Jiří - Kupčo, Alexander - Lokajíček, Miloš - Lysák, Roman - Marčišovský, Michal - Mikeštíková, Marcela - Němeček, Stanislav - Penc, Ondřej - Šícho, Petr - Staroba, Pavel - Svatoš, Michal - Taševský, Marek … Total 2888 authors
Measurement of the inclusive and fiducial tt¯ production cross-sections in the lepton+jets channel in pp collisions at √s=8 TeV with the ATLAS detector.
European Physical Journal C. Roč. 78, č. 6 (2018), s. 1-31, č. článku 487. ISSN 1434-6044. E-ISSN 1434-6052
R&D Projects: GA MŠMT(CZ) LTT17018
Institutional support: RVO:68378271
Keywords : ATLAS * CERN LHC Coll * phase space * particle identification: efficiency * background * experimental results * 8000 GeV-cms
OECD category: Particles and field physics
Impact factor: 4.843, year: 2018

The inclusive and fiducial tt¯ production cross-sections are measured in the lepton+jets channel using 20.2 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+,jets process is modelled using Z + jets events in a data-driven approach. The inclusive 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.) 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.) pb with a precision of 4.5%.

Permanent Link: http://hdl.handle.net/11104/0292424