Determination of the b -quark mass mbmb from the angular screening effects in the ATLAS b-jet shape data

The dependence of jet shapes in tt¯ events on the b-quark mass and the strong coupling is investigated. To this end, the Pythia Monte Carlo generator is used to produce samples of tt¯ events in pp   collisions at s=7TeV, performing a scan over the values for the shower QCD scale ΛsΛs and the b  -quark mass mbmb. The obtained jet shapes are compared with recently published data from the ATLAS Collaboration. From fits to the light-jet data, the Monte Carlo shower scale is determined, while the b-quark mass is extracted using the b-jet shapes. The result for the mass of the b  -quark is mb=4.86−0.42+0.49GeV.