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@PHDTHESIS{Martin:209916,
      author       = {Martin, Dirk},
      othercontributors = {Arcones Segovia, Almudena},
      title        = {r-process nucleosynthesis: on the astrophysical conditions
                      and the impact of nuclear physics input},
      school       = {TU Darmstadt},
      type         = {Dissertation},
      address      = {Darmstadt},
      publisher    = {TU Darmstadt},
      reportid     = {GSI-2018-00645},
      pages        = {113 p.},
      year         = {2017},
      note         = {Arcones Segovia, Prof. Dr. Almudena and Wambach, Prof. Dr.
                      Jochen; Dissertation, TU Darmstadt, 2017},
      abstract     = {The origin of the heaviest elements in our Universe is an
                      unresolved mystery. We know that half of the elements
                      heavier than iron are created by the rapid neutron capture
                      process (r-process). The r-process requires an extremely
                      neutron-rich environment as well as an explosive scenario.
                      Naturally, the merger of a neutron star with another compact
                      object provides suitable conditions. In particular, neutron
                      star mergers present the most promising astrophysical site
                      for the r-process.In this thesis, we study the r-process
                      nucleosynthesis in the material ejected from neutron star
                      mergers from two sites. First, we compute the detailed
                      r-process abundances for the different kinds of ejecta from
                      these systems, probing the astrophysical conditions. Second,
                      we determine the impact of the nuclear physics input on the
                      final abundance yields.For our comprehensive nucleosynthesis
                      study, we use hydrodynamical conditions from recent
                      astrophysical simulations of neutron star mergers in 3D. We
                      calculate for the first time the mass-integrated
                      nucleosynthesis yields of the dynamic ejecta and of the
                      neutrino-driven wind. The separation of timescales allows a
                      separate treatment of these two ejecta. We find that the
                      dynamic ejecta carry a substantial neutron-rich component to
                      produce a successful r-process. Since in all current
                      simulations only an approximate neutrino treatment is
                      computationally feasible, we explore the possible impact of
                      weak reactions. In our post-processing procedure, we see a
                      decrease in neutron-richness, such that a successful
                      r-process to the heaviest elements can be prevented. For the
                      subsequent neutrino-driven wind, we find that the
                      nucleosynthesis yields depend sensitively on both the life
                      time of the massive neutron star and the polar angle. Matter
                      in excess of up to $9 \cdot 10^{-3} M_\odot$ becomes unbound
                      until $\sim 200$~ms in the aftermath of the merger, similar
                      the ejected mass from the dynamic ejecta. Here, electron
                      fractions of $\Ye \approx 0.2 - 0.4$ lead to the production
                      of mainly nuclei with mass numbers $A < 130$. This
                      complements the yields from the earlier dynamic ejecta. We
                      consider mixing scenarios with these two types of ejecta to
                      explain the abundance pattern in r-process enriched
                      metal-poor stars. Additionally, we calculate heating rates
                      for the decay of the freshly produced radioactive isotopes.
                      The resulting light curve, known as kilonova, peaks in the
                      blue band after about four hours. Furthermore, high
                      opacities due to heavy r-process nuclei in the dynamic
                      ejecta lead to a second peak in the infrared after three to
                      four days.From the nuclear physics side, we investigate the
                      impact of the nuclear physics input on the nucleosynthesis.
                      Here, nuclear masses play a fundamental role in
                      understanding how the heaviest elements are created in the
                      r-process. Using masses obtained with six Skyrme energy
                      density functionals that are based on different optimization
                      protocols, we calculate neutron capture and
                      photodissociation rates. We predict r-process
                      nucleosynthesis yields in realistic astrophysical scenarios
                      and determine for the first time systematic uncertainty
                      bands for r-process abundances related to mass modeling. We
                      find that features of the underlying microphysics make an
                      imprint on abundances especially in the vicinity of neutron
                      shell closures. Abundance peaks and troughs are reflected in
                      the trends of neutron separation energy. Further advances in
                      the nuclear theory and experiments, when linked to
                      observations, will help in the understanding of
                      astrophysical conditions in extreme r-process sites.},
      cin          = {THE},
      cid          = {I:(DE-Ds200)THE-20051214OR028},
      pnm          = {612 - Cosmic Matter in the Laboratory (POF3-612) /
                      HGF-IVF-VH-GS-201 - HGS-HIRe : (HGF-IVF-VH-GS-201) /
                      HGF-IVF-VH-NG-825 - VH-NG-825 : Theorie, Core-collapse
                      supernovae: nuclei and matter at the extremes
                      (HGF-IVF-VH-NG-825)},
      pid          = {G:(DE-HGF)POF3-612 / G:(DE-Ds200)HGF-IVF-VH-GS-201 /
                      G:(DE-Ds200)HGF-IVF-VH-NG-825},
      typ          = {PUB:(DE-HGF)11},
      urn          = {urn:nbn:de:tuda-tuprints-63017},
      url          = {https://repository.gsi.de/record/209916},
}