Measurement of the top quark mass in the tt¯→ lepton+jets and tt¯→ dilepton channels using √s=7 TeV ATLAS data

Allbrooke, B M M, Asquith, L, Cerri, A, Chavez Barajas, C A, De Santo, A, Salvatore, F, Santoyo Castillo, I, Suruliz, K, Sutton, M R, Vivarelli, I and The ATLAS Collaboration, et al. (2015) Measurement of the top quark mass in the tt¯→ lepton+jets and tt¯→ dilepton channels using √s=7 TeV ATLAS data. European Physical Journal C - Particles and Fields, 75 (330). ISSN 1434-6044

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Abstract

The top quark mass was measured in the channels tt¯ → lepton+jets and tt¯ → dilepton (lepton = e,μ) based on ATLAS data recorded in 2011. The data were taken at the LHC with a proton–proton centre-of-mass energy of √s=7 TeV and correspond to an integrated luminosity of 4.6 fb−1. The tt¯ → lepton+jets analysis uses a three-dimensional template technique which determines the top quark mass together with a global jet energy scale factor (JSF), and a relative b-to-light-jet energy scale factor (bJSF), where the terms b-jets and light-jets refer to jets originating from b-quarks and u, d, c, s-quarks or gluons, respectively. The analysis of the tt¯ → dilepton channel exploits a one-dimensional template method using the m_b observable, defined as the average invariant mass of the two lepton+b-jet pairs in each event. The top quark mass is measured to be 172.33±0.75(stat + JSF + bJSF)± 1.02(syst) GeV, and 173.79 ± 0.54(stat) ± 1.30(syst) GeV in the tt¯ → lepton+jets and tt¯ → dilepton channels, respectively. The combination of the two results yields mtop = 172.99 ± 0.48(stat) ± 0.78(syst) GeV, with a total uncertainty of 0.91 GeV.

Item Type: Article
Schools and Departments: School of Mathematical and Physical Sciences > Physics and Astronomy
Research Centres and Groups: Experimental Particle Physics Research Group
Subjects: Q Science > QC Physics
Depositing User: Billy Wichaidit
Date Deposited: 27 Apr 2017 15:51
Last Modified: 28 Apr 2017 04:58
URI: http://sro.sussex.ac.uk/id/eprint/67552

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Project NameSussex Project NumberFunderFunder Ref
ATLASG0275STFC-SCIENCE AND TECHNOLOGY FACILITIES COUNCILST/I006048/1