Speaker
Christian Schwanenberger
(Deutsches Elektronen-Synchrotron (DE))
Description
The large centre-of-mass energy available at the
proton-proton collider LHC allows for the copious production of top
quark pairs in association with other final state particles at high
transverse momentum. The ATLAS experiment has measured several final
state observables that are sensitive to additional radiation in top
anti-top quark final states. Results on the top production in
association with W and Z bosons are presented along with measurements
of the cross section for production with an associated isolated
photon. Analyses probing the top pair production with additional QCD
radiation include the multiplicity of jets for various transverse
momentum thresholds or the probability to emit jets above a given
threshold in a fixed rapidity region. These measurements are compared
to modern Monte Carlo generators based on NLO QCD matrix element or LO
multi-leg matrix elements. The data are able to constrain the
uncertainty on the modelling of the top pair production mechanism. We
also discuss the production of top quark pairs in association with
additional b-jets.
Author
Dick Greenwood Jr
(Louisiana Tech University (US))
