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Phong VH, Nishimura S, Lorusso G, Davinson T, Estrade A, Hall O, Kawano T, Liu J, Montes F, Nishimura N, Grzywacz R, Rykaczewski KP, Agramunt J, Ahn DS, Algora A, Allmond JM, Baba H, Bae S, Brewer NT, Bruno CG, Caballero-Folch R, Calviño F, Coleman-Smith PJ, Cortes G, Dillmann I, Domingo-Pardo C, Fijalkowska A, Fukuda N, Go S, Griffin CJ, Ha J, Harkness-Brennan LJ, Isobe T, Kahl D, Khiem LH, Kiss GG, Korgul A, Kubono S, Labiche M, Lazarus I, Liang J, Liu Z, Matsui K, Miernik K, Moon B, Morales AI, Morrall P, Nepal N, Page RD, Piersa-Siłkowska M, Pucknell VFE, Rasco BC, Rubio B, Sakurai H, Shimizu Y, Stracener DW, Sumikama T, Suzuki H, Tain JL, Takeda H, Tarifeño-Saldivia A, Tolosa-Delgado A, Wolińska-Cichocka M, Woods PJ, Yokoyama R. β-Delayed One and Two Neutron Emission Probabilities Southeast of ^{132}Sn and the Odd-Even Systematics in r-Process Nuclide Abundances. PHYSICAL REVIEW LETTERS 2022; 129:172701. [PMID: 36332266 DOI: 10.1103/physrevlett.129.172701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2022] [Revised: 07/30/2022] [Accepted: 08/25/2022] [Indexed: 06/16/2023]
Abstract
The β-delayed one- and two-neutron emission probabilities (P_{1n} and P_{2n}) of 20 neutron-rich nuclei with N≥82 have been measured at the RIBF facility of the RIKEN Nishina Center. P_{1n} of ^{130,131}Ag, ^{133,134}Cd, ^{135,136}In, and ^{138,139}Sn were determined for the first time, and stringent upper limits were placed on P_{2n} for nearly all cases. β-delayed two-neutron emission (β2n) was unambiguously identified in ^{133}Cd and ^{135,136}In, and their P_{2n} were measured. Weak β2n was also detected from ^{137,138}Sn. Our results highlight the effect of the N=82 and Z=50 shell closures on β-delayed neutron emission probability and provide stringent benchmarks for newly developed macroscopic-microscopic and self-consistent global models with the inclusion of a statistical treatment of neutron and γ emission. The impact of our measurements on r-process nucleosynthesis was studied in a neutron star merger scenario. Our P_{1n} and P_{2n} have a direct impact on the odd-even staggering of the final abundance, improving the agreement between calculated and observed Solar System abundances. The odd isotope fraction of Ba in r-process-enhanced (r-II) stars is also better reproduced using our new data.
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Affiliation(s)
- V H Phong
- RIKEN Nishina Center, Wako, Saitama 351-0198, Japan
- University of Science, Vietnam National University, Hanoi 120062, Vietnam
| | - S Nishimura
- RIKEN Nishina Center, Wako, Saitama 351-0198, Japan
| | - G Lorusso
- RIKEN Nishina Center, Wako, Saitama 351-0198, Japan
- National Physical Laboratory, Teddington TW11 0LW, United Kingdom
- Department of Physics, University of Surrey, Guildford GU2 7XH, United Kingdom
| | - T Davinson
- School of Physics and Astronomy, University of Edinburgh, Edinburgh EH9 3FD, United Kingdom
| | - A Estrade
- Department of Physics, Central Michigan University, Mount Pleasant, Michigan 48859, USA
| | - O Hall
- School of Physics and Astronomy, University of Edinburgh, Edinburgh EH9 3FD, United Kingdom
| | - T Kawano
- Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - J Liu
- RIKEN Nishina Center, Wako, Saitama 351-0198, Japan
- Department of Physics, University of Hong Kong, Pokfulman Road, Hong Kong
| | - F Montes
- National Superconducting Cyclotron Laboratory, East Lansing, Michigan 48824, USA
| | - N Nishimura
- RIKEN Nishina Center, Wako, Saitama 351-0198, Japan
- Astrophysical Big-Bang Laboratory, Cluster for Pioneering Research, RIKEN, Wako, Saitama 351-0198, Japan
| | - R Grzywacz
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - K P Rykaczewski
- Physics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - J Agramunt
- Instituto de Fsica Corpuscular, CSIC and Universitat de Valencia, E-46980 Paterna, Spain
| | - D S Ahn
- RIKEN Nishina Center, Wako, Saitama 351-0198, Japan
- Center for Exotic Nuclear Studies, Institute for Basic Science, Daejeon 34126, Republic of Korea
| | - A Algora
- Instituto de Fsica Corpuscular, CSIC and Universitat de Valencia, E-46980 Paterna, Spain
| | - J M Allmond
- Physics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - H Baba
- RIKEN Nishina Center, Wako, Saitama 351-0198, Japan
| | - S Bae
- Center for Exotic Nuclear Studies, Institute for Basic Science, Daejeon 34126, Republic of Korea
| | - N T Brewer
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA
- Physics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - C G Bruno
- School of Physics and Astronomy, University of Edinburgh, Edinburgh EH9 3FD, United Kingdom
| | | | - F Calviño
- Universitat Politecnica de Catalunya, E-08028 Barcelona, Spain
| | - P J Coleman-Smith
- STFC Daresbury Laboratory, Daresbury, Warrington WA4 4AD, United Kingdom
| | - G Cortes
- Universitat Politecnica de Catalunya, E-08028 Barcelona, Spain
| | - I Dillmann
- TRIUMF, Vancouver, British Columbia V6T 2A3, Canada
- Department of Physics and Astronomy, University of Victoria, Victoria, British Columbia V8P 5C2, Canada
| | - C Domingo-Pardo
- Instituto de Fsica Corpuscular, CSIC and Universitat de Valencia, E-46980 Paterna, Spain
| | - A Fijalkowska
- Faculty of Physics, University of Warsaw, PL02-093 Warsaw, Poland
| | - N Fukuda
- RIKEN Nishina Center, Wako, Saitama 351-0198, Japan
| | - S Go
- RIKEN Nishina Center, Wako, Saitama 351-0198, Japan
| | - C J Griffin
- School of Physics and Astronomy, University of Edinburgh, Edinburgh EH9 3FD, United Kingdom
| | - J Ha
- RIKEN Nishina Center, Wako, Saitama 351-0198, Japan
- Seoul National University, Department of Physics and Astronomy, Seoul 08826, Republic of Korea
| | - L J Harkness-Brennan
- Department of Physics, University of Liverpool, Liverpool L69 7ZE, United Kingdom
| | - T Isobe
- RIKEN Nishina Center, Wako, Saitama 351-0198, Japan
| | - D Kahl
- School of Physics and Astronomy, University of Edinburgh, Edinburgh EH9 3FD, United Kingdom
- Extreme Light Infrastructure-Nuclear Physics, Horia Hulubei National Institute for R&D in Physics and Nuclear Engineering (IFIN-HH), 077125 Bucharest-Măgurele, Romania
| | - L H Khiem
- Institute of Physics, Vietnam Academy of Science and Technology, Ba Dinh, 118011 Hanoi, Vietnam
- Graduate University of Science and Technology, Vietnam Academy of Science and Technology, Cau Giay, 122102 Hanoi, Vietnam
| | - G G Kiss
- RIKEN Nishina Center, Wako, Saitama 351-0198, Japan
- Institute for Nuclear Research (Atomki), Debrecen H4032, Hungary
| | - A Korgul
- Faculty of Physics, University of Warsaw, PL02-093 Warsaw, Poland
| | - S Kubono
- RIKEN Nishina Center, Wako, Saitama 351-0198, Japan
| | - M Labiche
- STFC Daresbury Laboratory, Daresbury, Warrington WA4 4AD, United Kingdom
| | - I Lazarus
- STFC Daresbury Laboratory, Daresbury, Warrington WA4 4AD, United Kingdom
| | - J Liang
- McMaster University, Department of Physics and Astronomy, Hamilton, Ontario L8S 4M1, Canada
| | - Z Liu
- Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China
- School of Nuclear Science and Technology, University of Chinese Academy of Sciences, Beijing 100049, China
| | - K Matsui
- RIKEN Nishina Center, Wako, Saitama 351-0198, Japan
- University of Tokyo, Department of Physics, Tokyo 113-0033, Japan
| | - K Miernik
- Faculty of Physics, University of Warsaw, PL02-093 Warsaw, Poland
| | - B Moon
- Center for Exotic Nuclear Studies, Institute for Basic Science, Daejeon 34126, Republic of Korea
| | - A I Morales
- Instituto de Fsica Corpuscular, CSIC and Universitat de Valencia, E-46980 Paterna, Spain
| | - P Morrall
- STFC Daresbury Laboratory, Daresbury, Warrington WA4 4AD, United Kingdom
| | - N Nepal
- Department of Physics, Central Michigan University, Mount Pleasant, Michigan 48859, USA
| | - R D Page
- Department of Physics, University of Liverpool, Liverpool L69 7ZE, United Kingdom
| | | | - V F E Pucknell
- STFC Daresbury Laboratory, Daresbury, Warrington WA4 4AD, United Kingdom
| | - B C Rasco
- Physics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - B Rubio
- Instituto de Fsica Corpuscular, CSIC and Universitat de Valencia, E-46980 Paterna, Spain
| | - H Sakurai
- RIKEN Nishina Center, Wako, Saitama 351-0198, Japan
- University of Tokyo, Department of Physics, Tokyo 113-0033, Japan
| | - Y Shimizu
- RIKEN Nishina Center, Wako, Saitama 351-0198, Japan
| | - D W Stracener
- Physics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - T Sumikama
- RIKEN Nishina Center, Wako, Saitama 351-0198, Japan
| | - H Suzuki
- RIKEN Nishina Center, Wako, Saitama 351-0198, Japan
| | - J L Tain
- Instituto de Fsica Corpuscular, CSIC and Universitat de Valencia, E-46980 Paterna, Spain
| | - H Takeda
- RIKEN Nishina Center, Wako, Saitama 351-0198, Japan
| | - A Tarifeño-Saldivia
- Instituto de Fsica Corpuscular, CSIC and Universitat de Valencia, E-46980 Paterna, Spain
- Universitat Politecnica de Catalunya, E-08028 Barcelona, Spain
| | - A Tolosa-Delgado
- Instituto de Fsica Corpuscular, CSIC and Universitat de Valencia, E-46980 Paterna, Spain
| | - M Wolińska-Cichocka
- Heavy Ion Laboratory, University of Warsaw, Pasteura 5A, PL-02-093 Warsaw, Poland
| | - P J Woods
- School of Physics and Astronomy, University of Edinburgh, Edinburgh EH9 3FD, United Kingdom
| | - R Yokoyama
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA
- Center for Nuclear Study, University of Tokyo, RIKEN Campus, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
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Robin C, Litvinova E, Martínez-Pinedo G. Beyond-mean-field calculations of allowed and first-forbidden β− decays of r-process waiting-point nuclei. EPJ WEB OF CONFERENCES 2022. [DOI: 10.1051/epjconf/202226003002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
β-decay rates of neutron-rich nuclei, in particular those located at neutron shell closures, play a central role in simulations of the heavy-element nucleosynthesis and resulting abundance distributions. We present β-decay half-lives of even-even N = 82 and N = 126 r-process waiting-point nuclei calculated in the approach based on relativistic quasiparticle random phase approximation with quasiparticle-vibration coupling. The calculations include both allowed and first-forbidden transitions. In the N = 82 chain, the quasiparticlevibration coupling has an important impact close to stability, as it increases the contribution of Gamow-Teller modes and improves the agreement with the available data. In the N = 126 chain, we find the decay to proceed dominantly via first-forbidden transitions, even when the coupling to vibrations is included.
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Côté B, Eichler M, Yagüe López A, Vassh N, Mumpower MR, Világos B, Soós B, Arcones A, Sprouse TM, Surman R, Pignatari M, Pető MK, Wehmeyer B, Rauscher T, Lugaro M. 129I and 247Cm in meteorites constrain the last astrophysical source of solar r-process elements. Science 2021; 371:945-948. [PMID: 33632846 DOI: 10.1126/science.aba1111] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Accepted: 01/25/2021] [Indexed: 11/03/2022]
Abstract
The composition of the early Solar System can be inferred from meteorites. Many elements heavier than iron were formed by the rapid neutron capture process (r-process), but the astrophysical sources where this occurred remain poorly understood. We demonstrate that the near-identical half-lives [Formula: see text] of the radioactive r-process nuclei iodine-129 and curium-247 preserve their ratio, irrespective of the time between production and incorporation into the Solar System. We constrain the last r-process source by comparing the measured meteoritic ratio 129I/247Cm = 438 ± 184 with nucleosynthesis calculations based on neutron star merger and magneto-rotational supernova simulations. Moderately neutron-rich conditions, often found in merger disk ejecta simulations, are most consistent with the meteoritic value. Uncertain nuclear physics data limit our confidence in this conclusion.
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Affiliation(s)
- Benoit Côté
- Research Centre for Astronomy and Earth Sciences, Eötvös Loránd Research Network, Konkoly Observatory, 1121 Budapest, Hungary. .,Institute of Physics, Eötvös Loránd University, 1117 Budapest, Hungary.,National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, MI 48824, USA
| | - Marius Eichler
- Institut für Kernphysik, Technische Universität Darmstadt, 64289 Darmstadt, Germany
| | - Andrés Yagüe López
- Research Centre for Astronomy and Earth Sciences, Eötvös Loránd Research Network, Konkoly Observatory, 1121 Budapest, Hungary
| | - Nicole Vassh
- Department of Physics, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Matthew R Mumpower
- Theoretical Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA.,Center for Theoretical Astrophysics, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | - Blanka Világos
- Research Centre for Astronomy and Earth Sciences, Eötvös Loránd Research Network, Konkoly Observatory, 1121 Budapest, Hungary.,Institute of Physics, Eötvös Loránd University, 1117 Budapest, Hungary
| | - Benjámin Soós
- Research Centre for Astronomy and Earth Sciences, Eötvös Loránd Research Network, Konkoly Observatory, 1121 Budapest, Hungary.,Institute of Physics, Eötvös Loránd University, 1117 Budapest, Hungary
| | - Almudena Arcones
- Institut für Kernphysik, Technische Universität Darmstadt, 64289 Darmstadt, Germany.,GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291 Darmstadt, Germany
| | - Trevor M Sprouse
- Department of Physics, University of Notre Dame, Notre Dame, IN 46556, USA.,Theoretical Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | - Rebecca Surman
- Department of Physics, University of Notre Dame, Notre Dame, IN 46556, USA
| | - Marco Pignatari
- E.A. Milne Centre for Astrophysics, University of Hull, Hull HU6 7RX, UK.,Research Centre for Astronomy and Earth Sciences, Eötvös Loránd Research Network, Konkoly Observatory, 1121 Budapest, Hungary
| | - Mária K Pető
- Research Centre for Astronomy and Earth Sciences, Eötvös Loránd Research Network, Konkoly Observatory, 1121 Budapest, Hungary
| | - Benjamin Wehmeyer
- Research Centre for Astronomy and Earth Sciences, Eötvös Loránd Research Network, Konkoly Observatory, 1121 Budapest, Hungary.,Centre for Astrophysics Research, University of Hertfordshire, Hatfield AL10 9AB, UK
| | - Thomas Rauscher
- Centre for Astrophysics Research, University of Hertfordshire, Hatfield AL10 9AB, UK.,Department of Physics, University of Basel, 4056 Basel, Switzerland
| | - Maria Lugaro
- Research Centre for Astronomy and Earth Sciences, Eötvös Loránd Research Network, Konkoly Observatory, 1121 Budapest, Hungary.,Institute of Physics, Eötvös Loránd University, 1117 Budapest, Hungary.,Monash Centre for Astrophysics, School of Physics and Astronomy, Monash University, Clayton, VIC 3800, Australia
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4
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Sprouse TM, Mumpower MR, Surman R. Following Fission Products in Explosive Astrophysical Environments. EPJ WEB OF CONFERENCES 2020. [DOI: 10.1051/epjconf/202024204001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The astrophysical process by which the heaviest elements are formed in the universe is known as the rapid neutron capture process, or r process, of nucleosynthesis. The r process is characterized by the neutron capture and β− decay of short-lived, neutron-rich atomic nuclei; in suitably extreme environments, nuclear fission can also play a major role in determining the ensuing nucleosynthesis. In this work, we present the application of our recently developed nucleosynthesis tracing framework to precisely quantify the impact that neutron-induced and β− -delayed fission processes have in r-process environments that produce fissioning nuclei.
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Vassh N, Mumpower M, Sprouse T, Surman R, Vogt R. Probing the fission properties of neutron-rich actinides with the astrophysical r process. EPJ WEB OF CONFERENCES 2020. [DOI: 10.1051/epjconf/202024204002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
We review recent work examining the influence of fission in rapid neutron capture (r-process) nucleosynthesis which can take place in astrophysical environments. We briefly discuss the impact of uncertain fission barriers and fission rates on the population of heavy actinide species. We demonstrate the influence of the fission fragment distributions for neutron-rich nuclei and discuss currently available treatments, including recent macroscopic-microscopic calculations. We conclude by comparing our nucleosynthesis results directly with stellar data for metal-poor stars rich in r-process elements to consider whether fission plays a role in the so-called ‘universality’ of r-process abundances observed from star to star.
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Abstract
The coalescence of double neutron star (NS-NS) and black hole (BH)-NS binaries are prime sources of gravitational waves (GW) for Advanced LIGO/Virgo and future ground-based detectors. Neutron-rich matter released from such events undergoes rapid neutron capture (r-process) nucleosynthesis as it decompresses into space, enriching our universe with rare heavy elements like gold and platinum. Radioactive decay of these unstable nuclei powers a rapidly evolving, approximately isotropic thermal transient known as a "kilonova", which probes the physical conditions during the merger and its aftermath. Here I review the history and physics of kilonovae, leading to the current paradigm of day-timescale emission at optical wavelengths from lanthanide-free components of the ejecta, followed by week-long emission with a spectral peak in the near-infrared (NIR). These theoretical predictions, as compiled in the original version of this review, were largely confirmed by the transient optical/NIR counterpart discovered to the first NS-NS merger, GW170817, discovered by LIGO/Virgo. Using a simple light curve model to illustrate the essential physical processes and their application to GW170817, I then introduce important variations about the standard picture which may be observable in future mergers. These include ∼ hour-long UV precursor emission, powered by the decay of free neutrons in the outermost ejecta layers or shock-heating of the ejecta by a delayed ultra-relativistic outflow; and enhancement of the luminosity from a long-lived central engine, such as an accreting BH or millisecond magnetar. Joint GW and kilonova observations of GW170817 and future events provide a new avenue to constrain the astrophysical origin of the r-process elements and the equation of state of dense nuclear matter.
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Affiliation(s)
- Brian D. Metzger
- Department of Physics, Columbia Astrophysics Laboratory, Columbia University, New York, NY 10027 USA
- Center for Computational Astrophysics, Flatiron Institute, New York, NY 10010 USA
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Wang ZA, Pei J, Liu Y, Qiang Y. Bayesian Evaluation of Incomplete Fission Yields. PHYSICAL REVIEW LETTERS 2019; 123:122501. [PMID: 31633953 DOI: 10.1103/physrevlett.123.122501] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Revised: 07/16/2019] [Indexed: 06/10/2023]
Abstract
Fission product yields are key infrastructure data for nuclear applications in many aspects. It is a challenge both experimentally and theoretically to obtain accurate and complete energy-dependent fission yields. We apply the Bayesian neural network (BNN) approach to learn existing fission yields and predict unknowns with uncertainty quantification. We demonstrated that the BNN is particularly useful for evaluations of fission yields when incomplete experimental data are available. The BNN evaluation results are quite satisfactory on distribution positions and energy dependencies of fission yields.
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Affiliation(s)
- Zi-Ao Wang
- State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University, Beijing 100871, China
| | - Junchen Pei
- State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University, Beijing 100871, China
| | - Yue Liu
- State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University, Beijing 100871, China
| | - Yu Qiang
- State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University, Beijing 100871, China
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Neutron Star Mergers Might Not Be the Only Source of r-process Elements in the Milky Way. ACTA ACUST UNITED AC 2019. [DOI: 10.3847/1538-4357/ab10db] [Citation(s) in RCA: 107] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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9
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Binary Neutron Star Mergers: Mass Ejection, Electromagnetic Counterparts, and Nucleosynthesis. ACTA ACUST UNITED AC 2018. [DOI: 10.3847/1538-4357/aaf054] [Citation(s) in RCA: 212] [Impact Index Per Article: 35.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Schmidt KH, Jurado B. Review on the progress in nuclear fission-experimental methods and theoretical descriptions. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2018; 81:106301. [PMID: 29952321 DOI: 10.1088/1361-6633/aacfa7] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
An overview is given on some of the main advances in the experimental methods, experimental results, theoretical models and ideas of the last few years in the field of nuclear fission. New approaches have considerably extended the availability of fissioning systems for the experimental study of nuclear fission, and have provided a full identification of all fission products in A and Z for the first time. In particular, the transition from symmetric to asymmetric fission around 226Th, some unexpected structures in the mass distributions in the fission of systems around Z = 80-84, and an extended systematics of the odd-even effect in the fission fragment Z distributions have all been measured (Andreyev et al 2018 Rep. Prog. Phys. 81 016301). Three classes of model descriptions of fission presently appear to be the most promising or the most successful. Self-consistent quantum-mechanical models fully consider the quantum-mechanical features of the fission process. Intense efforts are presently being made to develop suitable theoretical tools (Schunck and Robledo 2016 Rep. Prog. Phys. 79 116301) for modeling the non-equilibrium, large-amplitude collective motion leading to fission. Stochastic models provide a fully developed technical framework. The main features of the fission-fragment mass distribution have been well reproduced from mercury to fermium and beyond (Möller and Randrup 2015 Phys. Rev. C 91 044316). However, limited computer resources still impose restrictions, for example, on the number of collective coordinates and on an elaborate description of the fission dynamics. In an alternative semi-empirical approach (Schmidt et al 2016 Nucl. Data Sheets 131 107), considerable progress in describing the fission observables has been achieved by combining several theoretical ideas, which are essentially well known. This approach exploits (i) the topological properties of a continuous function in multidimensional space, (ii) the separability of the influence of fragment shells and the macroscopic properties of the compound nucleus, (iii) the properties of a quantum oscillator coupled to a heat bath of other nuclear degrees of freedom, (iv) an early freeze-out of collective motion, and (v) the application of statistical mechanics for describing the thermalization of intrinsic excitations in the nascent fragments. This new approach reveals a high degree of regularity and allows the calculation of high-quality data that is relevant to nuclear technology without specifically adjusting the empirical data of individual systems.
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Affiliation(s)
- Karl-Heinz Schmidt
- CENBG, CNRS/IN2 P3, Chemin du Solarium B.P. 120, F-33175 Gradignan, France
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Fuller GM, Kusenko A, Takhistov V. Primordial Black Holes and r-Process Nucleosynthesis. PHYSICAL REVIEW LETTERS 2017; 119:061101. [PMID: 28949605 DOI: 10.1103/physrevlett.119.061101] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Indexed: 06/07/2023]
Abstract
We show that some or all of the inventory of r-process nucleosynthesis can be produced in interactions of primordial black holes (PBHs) with neutron stars (NSs) if PBHs with masses 10^{-14} M_{⊙}<M_{PBH}<10^{-8} M_{⊙} make up a few percent or more of dark matter. A PBH captured by a NS sinks to the center of the NS and consumes it from the inside. When this occurs in a rotating millisecond-period NS, the resulting spin-up ejects ∼0.1 M_{⊙}-0.5 M_{⊙} of relatively cold neutron-rich material. This ejection process and the accompanying decompression and decay of nuclear matter can produce electromagnetic transients, such as a kilonova-type afterglow and fast radio bursts. These transients are not accompanied by significant gravitational radiation or neutrinos, allowing such events to be differentiated from compact object mergers occurring within the distance sensitivity limits of gravitational-wave observatories. The PBH-NS destruction scenario is consistent with pulsar and NS statistics, the dark-matter content, and spatial distributions in the Galaxy and ultrafaint dwarfs, as well as with the r-process content and evolution histories in these sites. Ejected matter is heated by beta decay, which leads to emission of positrons in an amount consistent with the observed 511-keV line from the Galactic center.
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Affiliation(s)
- George M Fuller
- Department of Physics, University of California, San Diego, La Jolla, California 92093-0424, USA
| | - Alexander Kusenko
- Department of Physics and Astronomy, University of California, Los Angeles, Los Angeles, California 90095-1547, USA
- Kavli Institute for the Physics and Mathematics of the Universe (WPI), UTIAS, University of Tokyo, Kashiwa, Chiba 277-8583, Japan
| | - Volodymyr Takhistov
- Department of Physics and Astronomy, University of California, Los Angeles, Los Angeles, California 90095-1547, USA
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Kajino T, Mathews GJ. Impact of new data for neutron-rich heavy nuclei on theoretical models for r-process nucleosynthesis. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2017; 80:084901. [PMID: 28357989 DOI: 10.1088/1361-6633/aa6a25] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Current models for the r process are summarized with an emphasis on the key constraints from both nuclear physics measurements and astronomical observations. In particular, we analyze the importance of nuclear physics input such as beta-decay rates; nuclear masses; neutron-capture cross sections; beta-delayed neutron emission; probability of spontaneous fission, beta- and neutron-induced fission, fission fragment mass distributions; neutrino-induced reaction cross sections, etc. We highlight the effects on models for r-process nucleosynthesis of newly measured β-decay half-lives, masses, and spectroscopy of neutron-rich nuclei near the r-process path. We overview r-process nucleosynthesis in the neutrino driven wind above the proto-neutron star in core collapse supernovae along with the possibility of magneto-hydrodynamic jets from rotating supernova explosion models. We also consider the possibility of neutron star mergers as an r-process environment. A key outcome of newly measured nuclear properties far from stability is the degree of shell quenching for neutron rich isotopes near the closed neutron shells. This leads to important constraints on the sites for r-process nucleosynthesis in which freezeout occurs on a rapid timescale.
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Affiliation(s)
- Toshitaka Kajino
- International Research Center for Big-Bang Cosmology and Element Genesis, and School of Physics and Nuclear Energy Engineering, Beihang University, Beijing 100191, People's Republic of China. Division of Theoretical Astronomy, National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo, 181-8588, Japan. Department of Astronomy, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-033, Japan
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15
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The Intermediate r-process in Core-collapse Supernovae Driven by the Magneto-rotational Instability. ACTA ACUST UNITED AC 2017. [DOI: 10.3847/2041-8213/aa5dee] [Citation(s) in RCA: 103] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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16
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Abstract
The mergers of double neutron star (NS-NS) and black hole (BH)-NS binaries are promising gravitational wave (GW) sources for Advanced LIGO and future GW detectors. The neutron-rich ejecta from such merger events undergoes rapid neutron capture (r-process) nucleosynthesis, enriching our Galaxy with rare heavy elements like gold and platinum. The radioactive decay of these unstable nuclei also powers a rapidly evolving, supernova-like transient known as a "kilonova" (also known as "macronova"). Kilonovae are an approximately isotropic electromagnetic counterpart to the GW signal, which also provides a unique and direct probe of an important, if not dominant, r-process site. I review the history and physics of kilonovae, leading to the current paradigm of week-long emission with a spectral peak at near-infrared wavelengths. Using a simple light curve model to illustrate the basic physics, I introduce potentially important variations on this canonical picture, including: [Formula: see text]day-long optical ("blue") emission from lanthanide-free components of the ejecta; [Formula: see text]hour-long precursor UV/blue emission, powered by the decay of free neutrons in the outermost ejecta layers; and enhanced emission due to energy input from a long-lived central engine, such as an accreting BH or millisecond magnetar. I assess the prospects of kilonova detection following future GW detections of NS-NS/BH-NS mergers in light of the recent follow-up campaign of the LIGO binary BH-BH mergers.
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Affiliation(s)
- Brian D. Metzger
- Columbia Astrophysics Laboratory, Department of Physics, Columbia University, New York, NY USA
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17
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Caballero-Folch R, Domingo-Pardo C, Agramunt J, Algora A, Ameil F, Arcones A, Ayyad Y, Benlliure J, Borzov IN, Bowry M, Calviño F, Cano-Ott D, Cortés G, Davinson T, Dillmann I, Estrade A, Evdokimov A, Faestermann T, Farinon F, Galaviz D, García AR, Geissel H, Gelletly W, Gernhäuser R, Gómez-Hornillos MB, Guerrero C, Heil M, Hinke C, Knöbel R, Kojouharov I, Kurcewicz J, Kurz N, Litvinov YA, Maier L, Marganiec J, Marketin T, Marta M, Martínez T, Martínez-Pinedo G, Montes F, Mukha I, Napoli DR, Nociforo C, Paradela C, Pietri S, Podolyák Z, Prochazka A, Rice S, Riego A, Rubio B, Schaffner H, Scheidenberger C, Smith K, Sokol E, Steiger K, Sun B, Taín JL, Takechi M, Testov D, Weick H, Wilson E, Winfield JS, Wood R, Woods P, Yeremin A. First Measurement of Several β-Delayed Neutron Emitting Isotopes Beyond N=126. PHYSICAL REVIEW LETTERS 2016; 117:012501. [PMID: 27419564 DOI: 10.1103/physrevlett.117.012501] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Indexed: 06/06/2023]
Abstract
The β-delayed neutron emission probabilities of neutron rich Hg and Tl nuclei have been measured together with β-decay half-lives for 20 isotopes of Au, Hg, Tl, Pb, and Bi in the mass region N≳126. These are the heaviest species where neutron emission has been observed so far. These measurements provide key information to evaluate the performance of nuclear microscopic and phenomenological models in reproducing the high-energy part of the β-decay strength distribution. This provides important constraints on global theoretical models currently used in r-process nucleosynthesis.
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Affiliation(s)
- R Caballero-Folch
- INTE-DFEN, Universitat Politècnica de Catalunya, E-08028 Barcelona, Spain
- TRIUMF, Vancouver, British Columbia V6T2A3, Canada
| | | | - J Agramunt
- IFIC, CSIC-University of Valencia, E-46071 Valencia, Spain
| | - A Algora
- IFIC, CSIC-University of Valencia, E-46071 Valencia, Spain
- Institute of Nuclear Research of the Hungarian Academy of Sciences, Debrecen H-4001, Hungary
| | - F Ameil
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
| | - A Arcones
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
| | - Y Ayyad
- Universidade de Santiago de Compostela, E-15782 Santiago de Compostela, Spain
| | - J Benlliure
- Universidade de Santiago de Compostela, E-15782 Santiago de Compostela, Spain
| | - I N Borzov
- National Research Centre "Kurchatov Institute", 123182 Moscow, Russia
- Bogolubov Laboratory, Joint Institute for Nuclear Research, 141980 Dubna, Russia
| | - M Bowry
- Department of Physics, University of Surrey, Guildford GU2 7XH, United Kingdom
| | - F Calviño
- INTE-DFEN, Universitat Politècnica de Catalunya, E-08028 Barcelona, Spain
| | | | - G Cortés
- INTE-DFEN, Universitat Politècnica de Catalunya, E-08028 Barcelona, Spain
| | - T Davinson
- University of Edinburgh, EH9 3JZ Edinburgh, United Kingdom
| | - I Dillmann
- TRIUMF, Vancouver, British Columbia V6T2A3, Canada
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
- Justus-Liebig Universität Giessen, D-35392 Giessen, Germany
| | - A Estrade
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
- St. Mary's University, Halifax, B3H 3C3 Nova Scotia, Canada
| | - A Evdokimov
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
- Justus-Liebig Universität Giessen, D-35392 Giessen, Germany
| | - T Faestermann
- Physik Department E12, Technische Universität München, D-85748 Garching, Germany
| | - F Farinon
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
| | - D Galaviz
- Centro de Fisica Nuclear da Universidade de Lisboa, 169-003 Lisboa, Portugal
| | | | - H Geissel
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
- Justus-Liebig Universität Giessen, D-35392 Giessen, Germany
| | - W Gelletly
- Department of Physics, University of Surrey, Guildford GU2 7XH, United Kingdom
| | - R Gernhäuser
- Physik Department E12, Technische Universität München, D-85748 Garching, Germany
| | | | - C Guerrero
- CERN Physics Department, CH-1211 Geneve, Switzerland
- Universidad de Sevilla, 41080 Seville, Spain
| | - M Heil
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
| | - C Hinke
- Physik Department E12, Technische Universität München, D-85748 Garching, Germany
| | - R Knöbel
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
| | - I Kojouharov
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
| | - J Kurcewicz
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
| | - N Kurz
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
| | - Yu A Litvinov
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
| | - L Maier
- Physik Department E12, Technische Universität München, D-85748 Garching, Germany
| | - J Marganiec
- ExtreMe Matter Institute, 64291 Darmstadt, Germany
| | - T Marketin
- Department of Physics, Faculty of Science, University of Zagreb, 10000 Zagreb, Croatia
| | - M Marta
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
- Justus-Liebig Universität Giessen, D-35392 Giessen, Germany
| | | | - G Martínez-Pinedo
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
- Institut für Kernphysik (Theoriezentrum), Technische Universität Darmstadt, 64289 Darmstadt, Germany
| | - F Montes
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
- Joint Institute for Nuclear Astrophysics, Michigan State University, East Lansing, Michigan 48824, USA
| | - I Mukha
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
| | - D R Napoli
- Instituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, Legnaro I-35020, Italy
| | - C Nociforo
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
| | - C Paradela
- Universidade de Santiago de Compostela, E-15782 Santiago de Compostela, Spain
| | - S Pietri
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
| | - Zs Podolyák
- Department of Physics, University of Surrey, Guildford GU2 7XH, United Kingdom
| | - A Prochazka
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
| | - S Rice
- Department of Physics, University of Surrey, Guildford GU2 7XH, United Kingdom
| | - A Riego
- INTE-DFEN, Universitat Politècnica de Catalunya, E-08028 Barcelona, Spain
| | - B Rubio
- IFIC, CSIC-University of Valencia, E-46071 Valencia, Spain
| | - H Schaffner
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
| | - Ch Scheidenberger
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
- Justus-Liebig Universität Giessen, D-35392 Giessen, Germany
| | - K Smith
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
- National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
- Joint Institute for Nuclear Astrophysics, Michigan State University, East Lansing, Michigan 48824, USA
- University of Notre Dame, South Bend, Indiana 46556, USA
- University of Tennessee, Knoxville, Knoxville, Tennessee 37996, USA
| | - E Sokol
- Flerov Laboratory, Joint Institute for Nuclear Research, 141980 Dubna, Russia
| | - K Steiger
- Physik Department E12, Technische Universität München, D-85748 Garching, Germany
| | - B Sun
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
| | - J L Taín
- IFIC, CSIC-University of Valencia, E-46071 Valencia, Spain
| | - M Takechi
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
| | - D Testov
- Flerov Laboratory, Joint Institute for Nuclear Research, 141980 Dubna, Russia
- Institut de Physique Nucléaire d'Orsay, Orsay F-91405, France
| | - H Weick
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
| | - E Wilson
- Department of Physics, University of Surrey, Guildford GU2 7XH, United Kingdom
| | - J S Winfield
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, D-64291 Darmstadt, Germany
| | - R Wood
- Department of Physics, University of Surrey, Guildford GU2 7XH, United Kingdom
| | - P Woods
- University of Edinburgh, EH9 3JZ Edinburgh, United Kingdom
| | - A Yeremin
- Flerov Laboratory, Joint Institute for Nuclear Research, 141980 Dubna, Russia
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Martin D, Arcones A, Nazarewicz W, Olsen E. Impact of Nuclear Mass Uncertainties on the r Process. PHYSICAL REVIEW LETTERS 2016; 116:121101. [PMID: 27058066 DOI: 10.1103/physrevlett.116.121101] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Indexed: 06/05/2023]
Abstract
Nuclear masses play a fundamental role in understanding how the heaviest elements in the Universe are created in the r process. We predict r-process nucleosynthesis yields using neutron capture and photodissociation rates that are based on the nuclear density functional theory. Using six Skyrme energy density functionals based on different optimization protocols, we determine for the first time systematic uncertainty bands-related to mass modeling-for r-process abundances in realistic astrophysical scenarios. 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 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.
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Affiliation(s)
- D Martin
- Institut für Kernphysik, Technische Universität Darmstadt, Schlossgartenstrasse 2, Darmstadt D-64289, Germany
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, Planckstrasse 1, Darmstadt D-64291, Germany
| | - A Arcones
- Institut für Kernphysik, Technische Universität Darmstadt, Schlossgartenstrasse 2, Darmstadt D-64289, Germany
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, Planckstrasse 1, Darmstadt D-64291, Germany
| | - W Nazarewicz
- Department of Physics and Astronomy and FRIB Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
- Institute of Theoretical Physics, Faculty of Physics, University of Warsaw, 02-093 Warsaw, Poland
| | - E Olsen
- NSCL/FRIB Laboratory, Michigan State University, East Lansing, Michigan 48824, USA
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Martin D, Perego A, Arcones A, Thielemann FK, Korobkin O, Rosswog S. NEUTRINO-DRIVEN WINDS IN THE AFTERMATH OF A NEUTRON STAR MERGER: NUCLEOSYNTHESIS AND ELECTROMAGNETIC TRANSIENTS. ACTA ACUST UNITED AC 2015. [DOI: 10.1088/0004-637x/813/1/2] [Citation(s) in RCA: 159] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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