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@PHDTHESIS{Lenz:300800,
      author       = {Lenz, Teresa},
      othercontributors = {Sander, Christian and Schleper, Peter},
      title        = {{A} search for new heavy particles in events with highly
                      ionising, short tracks at the {CMS} experiment},
      issn         = {1435-8085},
      school       = {Universität Hamburg},
      type         = {Dissertation},
      address      = {Hamburg},
      publisher    = {Verlag Deutsches Elektronen-Synchrotron},
      reportid     = {PUBDB-2016-02420, DESY-THESIS-2016-016},
      series       = {DESY-THESIS},
      pages        = {223},
      year         = {2016},
      note         = {Dissertation, Universität Hamburg, 2016},
      abstract     = {The main focus of the CMS experiment at the Large Hadron
                      Collider (LHC) is to search for physics beyond the Standard
                      Model and to measure Standard Model parameters. For both
                      purposes it is essential to determine important performance
                      parameters of the CMS detector. The here presented thesis
                      contributes in a twofold way to the physics program of CMS.
                      In the first part of this thesis, a search for physics
                      beyond the Standard Model is presented. It is motivated by
                      supersymmetric models with nearly mass-degenerate lightest
                      neutralinos and lightest charginos. The small mass gap
                      between chargino and neutralino can lead to long lifetimes
                      of the chargino due to phase space suppression. Thus, the
                      chargino can reach the tracking system before its decay. The
                      here presented search targets chargino lifetimes of
                      $\text{c}\tau \approx 1 - 30\,\text{cm}$ where most of the
                      charginos decay in the first layers of the tracker. This
                      search aims at increasing the search sensitivity of existing
                      searches with respect to these models in a twofold way:
                      first, the inclusion of tracks down to three measurements in
                      the tracking system, and second, the discrimination against
                      Standard Model background by the energy loss per path
                      length. The search is performed on $19.7\,\text{fb}^{-1}$ of
                      data recorded at the CMS experiment at a centre-of-mass
                      energy of $8\,\text{TeV}$. No excess above the Standard
                      Model expectation is found and the supersymmetric parameter
                      space is constrained. The search can exclude supersymmetric
                      models with chargino masses of $100\,\text{GeV}$ down to
                      lifetimes of $\text{c}\tau=2\,\text{cm}$ and models with
                      masses of $500\,\text{GeV}$ down to lifetimes of
                      $\text{c}\tau=70\,\text{cm}$. Current limits are confirmed
                      and improvements of the order of $10-40\,\text{GeV}$ in
                      chargino mass are achieved. In the second part of the
                      thesis, a measurement of the jet transverse-momentum
                      resolution at $8\,\text{TeV}$ at the CMS experiment is
                      presented. In order to exploit the good energy resolution of
                      the electromagnetic calorimeter of the CMS detector, the
                      measurement is performed using $\gamma + \text{jet}$ events.
                      Due to the transverse momentum balance in the absence of
                      further jet activity, the photon momentum can be used as a
                      measure for the true jet transverse momentum. The applied
                      method is based on earlier measurements but is further
                      developed within this thesis in order to consistently
                      account for the influence of additional jet activity on the
                      jet transverse-momentum response. Relative differences of
                      the resolution in simulation and in data are measured
                      between 7\% and 20\%.},
      cin          = {UNI/EXP / CMS},
      cid          = {$I:(DE-H253)UNI_EXP-20120731$ / I:(DE-H253)CMS-20120731},
      pnm          = {899 - ohne Topic (POF3-899)},
      pid          = {G:(DE-HGF)POF3-899},
      experiment   = {EXP:(DE-H253)LHC-Exp-CMS-20150101},
      typ          = {PUB:(DE-HGF)3 / PUB:(DE-HGF)29 / PUB:(DE-HGF)11},
      doi          = {10.3204/DESY-THESIS-2016-016},
      url          = {https://bib-pubdb1.desy.de/record/300800},
}