Near-Barrier Elastic Scattering of Weakly Bound Nuclei and the Threshold Anomaly

Journal Article · Fri Oct 14 04:00:00 EDT 2005 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.2114702· OSTI ID:20719424

Hussein, M S; Chamon, L C ^[1]; Gomes, P R.S. ^[2]

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1. Instituto de Fisica, Universidade de Sao Paulo, Caixa Postal 66318, 05315-970 Sao Paulo, SP (Brazil)
2. Instituto de Fisica, Universidade Federal Fluminense, Av. Litoranea s/n, Gragoata, Niteroi, RJ, 24210-340 (Brazil)

It is pointed out that the usual threshold anomaly, found operative in the energy behavior of the imaginary and real parts of the optical potential representing the elastic scattering of tightly bound nuclei at near- and below-barrier energies, suffers a drastic qualitative change in the case of the elastic scattering of weakly bound projectile nuclei. Owing to the strong coupling to the breakup channel even at sub-barrier energies, the imaginary potential strength seems to increase as the energy is lowered down to below the natural, barrier, threshold, accompanied by a decrease in the real potential strength. This feature is consistent with the dispersion relation. It also clearly indicates the effective increase of the barrier height. The systems 9Be, 16O + 64Zn and 6,7Li + 138Ba are analyzed to illustrate this new phenomenon.

• OSTI ID: 20719424
• Journal Information: AIP Conference Proceedings, Journal Name: AIP Conference Proceedings Journal Issue: 1 Vol. 791; ISSN APCPCS; ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
BARIUM 138
BERYLLIUM 9
DISPERSION RELATIONS
ELASTIC SCATTERING
HEAVY IONS
LITHIUM 6
LITHIUM 7
NUCLEAR REACTIONS
OXYGEN 16
POTENTIALS
STRONG-COUPLING MODEL
ZINC 64