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Title: Sub-barrier fusion of neutron-rich nuclei and its astrophysical consequences

Abstract

Near-barrier fusion of neutron-rich nuclei was studied within the semiempirical channel coupling model for intermediate neutron rearrangement and within the time-dependent three-body Schroedinger equation. The possibility of neutron transfer with positive Q values considerably increases the barrier penetrability. A huge enhancement of deep sub-barrier fusion probability was found for light neutron-rich weakly bound nuclei (such as {sup 6}He). This may be quite important for astrophysical primordial and supernova nucleosynthesis.

Authors:
; ;  [1];  [2]
  1. Flerov Laboratory of Nuclear Reactions, JINR, Dubna, Moscow Region (Russian Federation)
  2. (Germany)
Publication Date:
OSTI Identifier:
20995176
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. C, Nuclear Physics; Journal Volume: 75; Journal Issue: 3; Other Information: DOI: 10.1103/PhysRevC.75.035809; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS; HEAVY ION FUSION REACTIONS; HELIUM 6; INTERMEDIATE NEUTRONS; NEUTRON TRANSFER; NEUTRON-RICH ISOTOPES; NUCLEAR MODELS; SCHROEDINGER EQUATION; SUPERNOVAE; THREE-BODY PROBLEM; TIME DEPENDENCE; VISIBLE RADIATION

Citation Formats

Zagrebaev, V. I., Samarin, V. V., Greiner, Walter, and Frankfurt Institute for Advanced Studies, J. W. Goethe-Universitaet, Frankfurt. Sub-barrier fusion of neutron-rich nuclei and its astrophysical consequences. United States: N. p., 2007. Web. doi:10.1103/PHYSREVC.75.035809.
Zagrebaev, V. I., Samarin, V. V., Greiner, Walter, & Frankfurt Institute for Advanced Studies, J. W. Goethe-Universitaet, Frankfurt. Sub-barrier fusion of neutron-rich nuclei and its astrophysical consequences. United States. doi:10.1103/PHYSREVC.75.035809.
Zagrebaev, V. I., Samarin, V. V., Greiner, Walter, and Frankfurt Institute for Advanced Studies, J. W. Goethe-Universitaet, Frankfurt. Thu . "Sub-barrier fusion of neutron-rich nuclei and its astrophysical consequences". United States. doi:10.1103/PHYSREVC.75.035809.
@article{osti_20995176,
title = {Sub-barrier fusion of neutron-rich nuclei and its astrophysical consequences},
author = {Zagrebaev, V. I. and Samarin, V. V. and Greiner, Walter and Frankfurt Institute for Advanced Studies, J. W. Goethe-Universitaet, Frankfurt},
abstractNote = {Near-barrier fusion of neutron-rich nuclei was studied within the semiempirical channel coupling model for intermediate neutron rearrangement and within the time-dependent three-body Schroedinger equation. The possibility of neutron transfer with positive Q values considerably increases the barrier penetrability. A huge enhancement of deep sub-barrier fusion probability was found for light neutron-rich weakly bound nuclei (such as {sup 6}He). This may be quite important for astrophysical primordial and supernova nucleosynthesis.},
doi = {10.1103/PHYSREVC.75.035809},
journal = {Physical Review. C, Nuclear Physics},
number = 3,
volume = 75,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}
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  • The β -decay half-lives of 110 neutron-rich isotopes of the elements from Rb 37 to Sn 50 were measured at the Radioactive Isotope Beam Factory. The 40 new half-lives follow robust systematics and highlight the persistence of shell effects. The new data have direct implications for r -process calculations and reinforce the notion that the second (A≈130 ) and the rare-earth-element (A≈160 ) abundance peaks may result from the freeze-out of an (n,γ)⇌(γ,n) equilibrium. In such an equilibrium, the new half-lives are important factors determining the abundance of rare-earth elements, and allow for a more reliable discussion of the rmore » process universality. It is anticipated that universality may not extend to the elements Sn, Sb, I, and Cs, making the detection of these elements in metal-poor stars of the utmost importance to determine the exact conditions of individual r -process events.« less
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