% IMPORTANT: The following is UTF-8 encoded.  This means that in the presence
% of non-ASCII characters, it will not work with BibTeX 0.99 or older.
% Instead, you should use an up-to-date BibTeX implementation like “bibtex8” or
% “biber”.

@PHDTHESIS{Chokoufe:331219,
      author       = {Chokoufe, Bijan},
      othercontributors = {Reuter, Juergen and Moch, Sven-Olaf},
      title        = {{S}crutinizing the {T}op {Q}uark at {L}epton {C}olliders
                      with {H}igher {O}rders},
      school       = {Universität Hamburg},
      type         = {Dissertation},
      address      = {Hamburg},
      publisher    = {Verlag Deutsches Elektronen-Synchrotron},
      reportid     = {PUBDB-2017-07624, DESY-THESIS-2017-029},
      series       = {DESY-THESIS},
      pages        = {177},
      year         = {2017},
      note         = {Dissertation, Universität Hamburg, 2017},
      abstract     = {In this thesis, we present detailed studies of top-pair
                      production with($t \bar t H$) and without association of a
                      Higgs boson ($t \bar t$) in$e^+e^-$ collisions.These
                      processes are of utmost interest for the top physics
                      programof future lepton colliders.They allow in particular a
                      precise measurement of the top quark mass andthe Yukawa
                      coupling.For this purpose, we present predictions for
                      off-shell $t \bar t$ and$t \bar t H$ production including
                      non-resonant and interferencecontributions up to
                      next-to-leading order (NLO) in perturbative quantum
                      chromodynamics (QCD).This allows for top-quark phenomenology
                      in the continuum at anunprecedented level of accuracy.We
                      show that off-shell effects and NLO QCD corrections forthese
                      processes do not factorize in general.In particular, we
                      present the Yukawa coupling dependence of the crosssection,
                      which receives negative corrections due to sizable
                      interferenceterms.We also add a discussion of $\p_T$
                      resummation in the form ofcombining the NLO prediction via
                      \textsc{Powheg} matching with the partonshower and the
                      associated uncertainties.To handle large Coulomb
                      singularities at threshold, we include thenext-to-leading
                      log (NLL) threshold resummation derived in nonrelativistic
                      QCD (NRQCD) for $t \bar t$ production.This results in a form
                      factor that we incorporate in a fullyrelativistic cross
                      section, which is factorized within an extendeddouble-pole
                      approximation.Fixed-order QCD corrections are included,
                      hereby, for the top decay.We combine this calculation with
                      the full fixed-order QCD results at NLO for $W^+b W^-\bar b$
                      production to obtain a computation that is not onlyvalid at
                      threshold but smoothly interpolates to the continuum.This
                      allows us to present the first prediction for exclusive
                      $W^+b W^-\bar b$production at a lepton collider with a
                      consistent matching between thetop-antitop threshold and
                      continuum regions.This computation is not only required to
                      describe the intermediateenergy region but also allows to
                      study threshold resummation effects infully differential
                      distributions and incorporates important electroweakand
                      relativistic corrections.All computations are implemented
                      within the automated NLO MonteCarlo event generator
                      \textsc{Whizard}.Thus, we review the important aspects of
                      the program and variousnew features that we have
                      implemented.},
      cin          = {T},
      cid          = {I:(DE-H253)T-20120731},
      pnm          = {611 - Fundamental Particles and Forces (POF3-611) / PHGS,
                      VH-GS-500 - PIER Helmholtz Graduate School
                      $(2015_IFV-VH-GS-500)$},
      pid          = {G:(DE-HGF)POF3-611 / $G:(DE-HGF)2015_IFV-VH-GS-500$},
      experiment   = {EXP:(DE-MLZ)NOSPEC-20140101},
      typ          = {PUB:(DE-HGF)3 / PUB:(DE-HGF)11},
      doi          = {10.3204/PUBDB-2017-07624},
      url          = {https://bib-pubdb1.desy.de/record/331219},
}