Date of Award
2014
Degree Type
Dissertation
Degree Name
Doctor of Philosophy (PhD)
Graduate Group
Physics & Astronomy
First Advisor
Elliot Lipeles
Abstract
Evidence for the Higgs boson is presented in the \hwwlnln\ channel in the ATLAS
detector with 20.3/fb of 8 TeV and 4.5/fb of
7 TeV proton-proton collisions at the Large Hadron Collider (LHC). The H$\rightarrow$WW analysis is one of the
three Higgs boson decay channels used by the ATLAS collaboration in combination to discover the
Higgs boson. As the LHC increased its instantaneous luminosity,
the average number of collisions per proton bunch crossing, called pileup, was
increased to around 20. The techniques presented in this thesis mitigate the
effects of pileup such as interaction vertex matching for event level
quantities such as the missing transverse momentum.
Optimization procedures for lepton identification, which is crucial for
the semi-leptonic W decays, are presented and methods to model the
fake leptons which are quarks
and gluons imitating leptons from W and Z bosons. Finally,
performance projections for future LHC running
conditions are explored to inform funding agencies.
These techniques
are applied to the gluon-gluon fusion (ggF) and vector boson fusion (VBF)
production of the Higgs boson on the LHC. Both production modes were
measured to be consistent with the Standard Model expectations.
Recommended Citation
Schaefer, Douglas Michael, "Evidence for the Higgs boson in the H->WW->lnulnu decay channel" (2014). Publicly Accessible Penn Dissertations. 1434.
https://repository.upenn.edu/edissertations/1434