000209916 001__ 209916
000209916 005__ 20260319125920.0
000209916 0247_ $$2URN$$aurn:nbn:de:tuda-tuprints-63017
000209916 037__ $$aGSI-2018-00645
000209916 041__ $$aEnglish
000209916 1001_ $$0P:(DE-HGF)0$$aMartin, Dirk$$b0$$eCorresponding author$$gmale
000209916 245__ $$ar-process nucleosynthesis: on the astrophysical conditions and the impact of nuclear physics input 
000209916 260__ $$aDarmstadt$$bTU Darmstadt$$c2017
000209916 300__ $$a113 p.
000209916 3367_ $$2DataCite$$aOutput Types/Dissertation
000209916 3367_ $$2ORCID$$aDISSERTATION
000209916 3367_ $$2BibTeX$$aPHDTHESIS
000209916 3367_ $$02$$2EndNote$$aThesis
000209916 3367_ $$0PUB:(DE-HGF)11$$2PUB:(DE-HGF)$$aDissertation / PhD Thesis$$bphd$$mphd$$s1526838432_7725
000209916 3367_ $$2DRIVER$$adoctoralThesis
000209916 500__ $$aArcones Segovia, Prof. Dr. Almudena and Wambach, Prof. Dr. Jochen
000209916 502__ $$aDissertation, TU Darmstadt, 2017$$bDissertation$$cTU Darmstadt$$d2017$$o2017-05-29
000209916 520__ $$aThe 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.
000209916 536__ $$0G:(DE-HGF)POF3-612$$a612 - Cosmic Matter in the Laboratory (POF3-612)$$cPOF3-612$$fPOF III$$x0
000209916 536__ $$0G:(DE-Ds200)HGF-IVF-VH-GS-201$$aHGF-IVF-VH-GS-201 - HGS-HIRe : (HGF-IVF-VH-GS-201)$$cHGF-IVF-VH-GS-201$$x1
000209916 536__ $$0G:(DE-Ds200)HGF-IVF-VH-NG-825$$aHGF-IVF-VH-NG-825 - VH-NG-825 : Theorie, Core-collapse supernovae: nuclei and matter at the extremes (HGF-IVF-VH-NG-825)$$cHGF-IVF-VH-NG-825$$x2
000209916 7001_ $$0P:(DE-Ds200)OR2242$$aArcones Segovia, Almudena$$b1$$eThesis advisor$$ugsi
000209916 909CO $$ooai:repository.gsi.de:209916$$pVDB
000209916 9101_ $$0I:(DE-HGF)0$$6P:(DE-HGF)0$$a TU Darmstadt$$b0
000209916 9101_ $$0I:(DE-Ds200)20121206GSI$$6P:(DE-Ds200)OR2242$$aGSI Helmholtzzentrum für Schwerionenforschung GmbH$$b1$$kGSI
000209916 9131_ $$0G:(DE-HGF)POF3-612$$1G:(DE-HGF)POF3-610$$2G:(DE-HGF)POF3-600$$3G:(DE-HGF)POF3$$4G:(DE-HGF)POF$$aDE-HGF$$bForschungsbereich Materie$$lMaterie und Universum$$vCosmic Matter in the Laboratory$$x0
000209916 9132_ $$0G:(DE-HGF)POF4-612$$1G:(DE-HGF)POF4-610$$2G:(DE-HGF)POF4-600$$3G:(DE-HGF)POF4$$4G:(DE-HGF)POF$$aDE-HGF$$bForschungsbereich Materie$$lMatter and the Universe$$vCosmic Matter in the Laboratory$$x0
000209916 9141_ $$y2017
000209916 920__ $$lno
000209916 9201_ $$0I:(DE-Ds200)THE-20051214OR028$$kTHE$$lTheorie$$x0
000209916 980__ $$aphd
000209916 980__ $$aVDB
000209916 980__ $$aI:(DE-Ds200)20120319OR028
000209916 980__ $$aI:(DE-Ds200)THE-20051214OR028
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