The Role of Fission in Neutron Star Mergers and Its Impact on the r-Process Peaks
Dateien
[The Role of Fission in Neutron Star Mergers and its Impact on the r-Process Peaks]
Autor:innen
Eichler, Marius
Arcones, Almudena
Kelic, Alexandra
Korobkin, Oleg
Langanke, Karlheinz
Marketin, Tomislav
Martinez-Pinedo, Gabriel
Panov, Igor
Rauscher, Thomas
Rosswog, Stephan
Autor:in (Körperschaft)
Publikationsdatum
15.07.2015
Typ der Arbeit
Studiengang
Typ
01A - Beitrag in wissenschaftlicher Zeitschrift
Herausgeber:innen
Herausgeber:in (Körperschaft)
Betreuer:in
Übergeordnetes Werk
The Astrophysical Journal
Themenheft
DOI der Originalpublikation
Link
Reihe / Serie
Reihennummer
Jahrgang / Band
808
Ausgabe / Nummer
1
Seiten / Dauer
13-43
Patentnummer
Verlag / Herausgebende Institution
The American Astronomical Society
Verlagsort / Veranstaltungsort
Washington
Auflage
Version
Programmiersprache
Abtretungsempfänger:in
Praxispartner:in/Auftraggeber:in
Zusammenfassung
Comparing 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.
Schlagwörter
nucleosynthesis, stars:neutron, r-process
Fachgebiet (DDC)
530 - Physik
Veranstaltung
Startdatum der Ausstellung
Enddatum der Ausstellung
Startdatum der Konferenz
Enddatum der Konferenz
Datum der letzten Prüfung
ISBN
ISSN
1538-4357
0004-637X
0004-637X
Sprache
Englisch
Während FHNW Zugehörigkeit erstellt
Ja
Zukunftsfelder FHNW
Publikationsstatus
Veröffentlicht
Begutachtung
Peer-Review der ganzen Publikation
Open Access-Status
Lizenz
Zitation
EICHLER, Marius, Almudena ARCONES, Alexandra KELIC, Oleg KOROBKIN, Karlheinz LANGANKE, Tomislav MARKETIN, Gabriel MARTINEZ-PINEDO, Igor PANOV, Thomas RAUSCHER, Stephan ROSSWOG, Christian WINTELER, Nikolaj ZINNER und Friedrich-Karl THIELEMANN, 2015. The Role of Fission in Neutron Star Mergers and Its Impact on the r-Process Peaks. The Astrophysical Journal. 15 Juli 2015. Bd. 808, Nr. 1, S. 13–43. DOI 10.1088/0004-637X/808/1/30. Verfügbar unter: https://doi.org/10.26041/fhnw-167