Collider Cross Talk

Determination of the top-quark mass from the lepton-b-jet mass distribution from CMS

Name: Determination of the top-quark mass from the lepton-b-jet mass distribution from CMS
Start: 2015-01-22T11:00:00+01:00
End: 2015-01-22T12:00:00+01:00
Location: CERN

by Jan Kieseler (Deutsches Elektronen-Synchrotron (DE))

Thursday 22 Jan 2015, 11:00 → 12:00 Europe/Zurich

4/2-011 - TH common room (CERN)

4/2-011 - TH common room

CERN

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Description

A measurement of the top-quark mass is presented using the distribution of the invariant mass mlb of the lepton and the b-quark originating from top-quark decays. The analysed dataset of pp-collisions at a centre-of-mass energy s√=8 TeV was recorded by the CMS experiment at the LHC, and corresponds to an integrated luminosity of 19.7 fb−1. Top-quark pair candidate events are selected with two opposite-charge isolated leptons, one electron and one muon, and at least two jets in the final state. Using the mlb shape prediction from MadGraph a top-quark mass of 172.3±1.3 GeV is obtained, consistent with previous measurements and with the world average. In addition, a study is presented in which the shape and/or normalisation of the measured mlb distribution are used to extract the top-quark mass using different theory predictions, the MadGraph simulation as well as a fixed-order QCD calculation.