Eichler, MariusArcones, AlmudenaKelic, AlexandraKorobkin, OlegLanganke, KarlheinzMarketin, TomislavMartinez-Pinedo, GabrielPanov, IgorRauscher, ThomasRosswog, StephanWinteler, ChristianZinner, NikolajThielemann, Friedrich-Karl2015-12-042015-12-042015-07-151538-43570004-637X10.1088/0004-637X/808/1/30http://hdl.handle.net/11654/11586https://doi.org/10.26041/fhnw-167Comparing observational abundance features with nucleosynthesis predictions of stellar evolution or explosion simulations can scrutinize two aspects: (a) the conditions in the astrophysical production site and (b) the quality of the nuclear physics input utilized. We test the abundance features of r-process nucleosynthesis calculations for the dynamical ejecta of neutron star merger simulations based on three different nuclear mass models: The Finite Range Droplet Model (FRDM), the (quenched version of the) Extended Thomas Fermi Model with Strutinsky Integral (ETFSI-Q), and the Hartree-Fock-Bogoliubov (HFB) mass model. We make use of corresponding fission barrier heights and compare the impact of four different fission fragment distribution models on the final r-process abundance distribution. In particular, we explore the abundance distribution in the second r-process peak and the rare-earth sub-peak as a function of mass models and fission fragment distributions, as well as the origin of a shift in the third r-process peak position. The latter has been noticed in a number of merger nucleosynthesis predictions. We show that the shift occurs during the r-process freeze-out when neutron captures and β-decays compete and an (n,γ)-(γ,n) equilibrium is not maintained anymore. During this phase neutrons originate mainly from fission of material above A = 240. We also investigate the role of β-decay half-lives from recent theoretical advances, which lead either to a smaller amount of fissioning nuclei during freeze-out or a faster (and thus earlier) release of fission neutrons, which can (partially) prevent this shift and has an impact on the second and rare-earth peak as well.ennucleosynthesisstars:neutronr-process530 - Physik01A - Beitrag in wissenschaftlicher Zeitschrift13-43