Measurement of the top quark mass using proton-proton data at √ ( s ) = 7 and 8 TeV

Abstract

A new set of measurements of the top quark mass are presented, based on the proton-proton data recorded by the CMS experiment at the LHC at √ s = 8 TeV corresponding to a luminosity of 19.7 fb − 1 . The top quark mass is measured using the lepton + jets , all-jets and dilepton decay channels, giving values of 172.35 ± 0.16 ( stat ) ± 0.48 ( syst ) GeV , 172.32 ± 0.25 ( stat ) ± 0.59 ( syst ) GeV , and 172.82 ± 0.19 ( stat ) ± 1.22 ( syst ) GeV , respectively. When combined with the published CMS results at √ s = 7 TeV , they provide a top quark mass measurement of 172.44 ± 0.13 ( stat ) ± 0.47 ( syst ) GeV . The top quark mass is also studied as a function of the event kinematical properties in the lepton + jets decay channel. No indications of a kinematic bias are observed and the collision data are consistent with a range of predictions from current theoretical models of t ¯ t production.