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Title: Sub-barrier Fusion of Weakly Bound Nuclei

Abstract

Near-barrier fusion of neutron reach nuclei was studied within the semi-empirical channel coupling model of intermediate neutron rearrangement and within the time dependent three-body Schroedinger equation. A 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 reach weakly bound nuclei (such as 6He) that may be extremely important for astrophysical primordial and supernova nucleosynthesis.

Authors:
 [1]
  1. Flerov Laboratory of Nuclear Reaction, JINR, Dubna, 141980, Moscow region (Russian Federation)
Publication Date:
OSTI Identifier:
21061839
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 912; Journal Issue: 1; Conference: International symposium on exotic nuclei, Khanty-Mansiysk (Russian Federation), 17-22 Jul 2006; Other Information: DOI: 10.1063/1.2746581; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ASTROPHYSICS; COUPLING; HELIUM 6; INTERMEDIATE NEUTRONS; NEUTRON TRANSFER; NUCLEOSYNTHESIS; PROBABILITY; Q-VALUE; SCHROEDINGER EQUATION; SUPERNOVAE; THREE-BODY PROBLEM; TIME DEPENDENCE

Citation Formats

Zagrebaev, Valery. Sub-barrier Fusion of Weakly Bound Nuclei. United States: N. p., 2007. Web. doi:10.1063/1.2746581.
Zagrebaev, Valery. Sub-barrier Fusion of Weakly Bound Nuclei. United States. doi:10.1063/1.2746581.
Zagrebaev, Valery. Tue . "Sub-barrier Fusion of Weakly Bound Nuclei". United States. doi:10.1063/1.2746581.
@article{osti_21061839,
title = {Sub-barrier Fusion of Weakly Bound Nuclei},
author = {Zagrebaev, Valery},
abstractNote = {Near-barrier fusion of neutron reach nuclei was studied within the semi-empirical channel coupling model of intermediate neutron rearrangement and within the time dependent three-body Schroedinger equation. A 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 reach weakly bound nuclei (such as 6He) that may be extremely important for astrophysical primordial and supernova nucleosynthesis.},
doi = {10.1063/1.2746581},
journal = {AIP Conference Proceedings},
number = 1,
volume = 912,
place = {United States},
year = {Tue May 22 00:00:00 EDT 2007},
month = {Tue May 22 00:00:00 EDT 2007}
}
  • Results of measurement of residues formed in fusion of {sup 6}Li with {sup 198}Pt in the energy range of 0.68<E/V{sub b}<1.3 using a new sensitive off-beam technique are reported. The fusion excitation function and the derived average angular momenta do not indicate a change of slope at deep sub-barrier energies, contrary to recent observations. The present results for a system with weakly bound projectile confront the current understanding of the fusion hindrance at these low energies, underlying the role of internal reorganization on the dynamical path towards fusion.
  • The influence on fusion of coupling to the breakup process is investigated for reactions where at least one of the colliding nuclei has a sufficiently low binding energy for breakup to become an important process. Elastic scattering, excitation functions for sub- and near-barrier fusion cross sections, and breakup yields are analyzed for {sup 6,7}Li+{sup 59}Co. Continuum-discretized coupled-channels (CDCC) calculations describe well the data at and above the barrier. Elastic scattering with {sup 6}Li (as compared to {sup 7}Li) indicates the significant role of breakup for weakly bound projectiles. A study of {sup 4,6}He induced fusion reactions with a three-body CDCCmore » method for the {sup 6}He halo nucleus is presented. The relative importance of breakup and bound-state structure effects on total fusion is discussed.« less
  • The effect of breakup is investigated for the medium weight 6Li+59Co system in the vicinity of the Coulomb barrier. The strong coupling of breakup/transfer channels to fusion is discussed within a comparison of predictions of the Continuum Discretized Coupled-Channels model which is also applied to 6He+59Co a reaction induced by the borromean halo nucleus 6He.
  • The influence on the fusion process of coupling transfer/breakup channels is investigated for the medium weight {sup 6,7}Li+{sup 59}Co systems in the vicinity of the Coulomb barrier. Coupling effects are discussed within a comparison of predictions of the Continuum Discretized Coupled-Channels model. Applications to {sup 6}He+{sup 59}Co induced by the borromean halo nucleus {sup 6}He are also proposed.
  • The radial sensitivity of elastic scattering for weakly bound ({sup 6}Li, {sup 7}Li, {sup 9}Be) and tightly bound projectiles ({sup 12}C, {sup 16}O) on light and heavy targets ({sup 28}Si, {sup 58}Ni, {sup 118}Sn, {sup 208}Pb, {sup 209}Bi) is sought at barrier energies, taking into account a Woods -Saxon potential and a BDM3Y1 interaction. The results are discussed in terms of the potential anomaly at the coulomb barrier.