% 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{Herzkamp:829945,
      author       = {Herzkamp, Matthias},
      title        = {{S}imulation and {O}ptimizationof a {P}osition {S}ensitive
                      {S}cintillation{D}etector with {W}avelength
                      {S}hifting{F}ibers for {T}hermal {N}eutrons},
      volume       = {4397},
      school       = {RWTH Aachen University},
      type         = {Dr.},
      address      = {Jülich},
      publisher    = {Forschungszentrum Jülich GmbH Zentralbibliothek, Verlag},
      reportid     = {FZJ-2017-03549, Juel-4397},
      series       = {Berichte des Forschungszentrums Jülich},
      pages        = {113 p.},
      year         = {2016},
      note         = {RWTH Aachen University, Diss., 2016},
      abstract     = {Due to the worldwide shortage of 3He and the price
                      development caused by this, alternativeconcepts of neutron
                      detection are in demand. One possible alternative is
                      aZnS/LiF scintillation detector with readout via wavelength
                      shifting fibers. The presenteddissertation describes the
                      development of a model of the physical frontend, which
                      enablescomputer-aided simulations with different
                      configurations and conditions.The model regards the
                      microscopic structure of the scintillator during the
                      trackingof alpha and triton particles created by the
                      conversion of a neutron at a 6Li as well asthe propagation
                      of photons through the scintillator plate. In the first
                      case, the structureis simulated via randomly placed
                      spherical grains, through which the charged
                      secondaryparticles are tracked. In the second case, the
                      photons are subject to a random walk withparameters
                      dependend on the composition of the scintillator.The model
                      is validated in several steps, during which single aspects
                      of the model areverified. There is a good agreement between
                      measurements and simulations of neutronabsorption and pulse
                      height spectra of different scintillator samples.A
                      comparison with optical transmission measurements shows,
                      that the simulated effectiveoptical absorption coefficent is
                      of the same order of magnitude as the measuredvalue of
                      samples of one manufacturer, but is smaller by a factor of 6
                      than the value ofsamples of another manufacturer.For the
                      validation of the entire model, measurements of a prototype
                      are compared tosimulations. In order to compare the data
                      event-wise, a detection algorithm based oncluster finding is
                      developed. Measurements and simulations are in good
                      agreement, so themodel can be regarded as validated.To
                      optimize multiple parameters at the same time, a
                      generalization of the GoldenSection Search can be used. This
                      algorithm optimizes parameters with respect to an
                      optimizationfunction, e.g. detection effciency, which is
                      calculated dependend on simulationdata. This way it is
                      possible to optimize detector parameters for new
                      developments.},
      cin          = {ZEA-2},
      cid          = {I:(DE-Juel1)ZEA-2-20090406},
      pnm          = {899 - ohne Topic (POF3-899)},
      pid          = {G:(DE-HGF)POF3-899},
      typ          = {PUB:(DE-HGF)3 / PUB:(DE-HGF)29 / PUB:(DE-HGF)11},
      url          = {https://juser.fz-juelich.de/record/829945},
}