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# Measurement of the top-quark mass in the fully hadronic decay channel from ATLAS data at $$\sqrt{s}=7$$ TeV

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### Abstract

The mass of the top quark is measured in a data set corresponding to 4.6 fb$$^{-1}$$ of proton-proton collisions with centre-of-mass energy $$\sqrt{s}=7$$ TeV collected by the ATLAS detector at the LHC. Events consistent with hadronic decays of top-antitop quark pairs with at least six jets in the final state are selected. The substantial background from multijetproduction is modelled with data-driven methods that utilise the number of identified $$b$$-quark jets and the transverse momentum of the sixth leading jet,which have minimal correlation. The top-quark mass is obtained from template fits to the ratio of three-jet to dijet mass. The three-jet mass is calculated from the three jets produced in a top-quark decay. Using these three jets the dijet mass is obtained from the two jets produced in the $$W$$ boson decay. The top-quark mass obtained from this fit is thus less sensitive to the uncertainty in the energy measurement of the jets. A binned likelihood fit yields a top-quark mass of $$m_{t} = 175.1 \pm 1.4$$ (stat) $$\pm 1.2$$ (syst) GeV.

### Most cited references10

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### Author and article information

###### Journal
1409.0832
10.1140/epjc/s10052-015-3373-1
4446089

High energy & Particle physics