The 8Li(p, α)5He reaction at low energies, and 9Be spectroscopy around the proton threshold

被引：12

作者：

Mendes, D. R., Jr. ^{[1
]}

Lepine-Szily, A. ^{[1
]}

Descouvemont, P. ^{[2
]}

Lichtenthaeler, R. ^{[1
]}

Guimaraes, V. ^{[1
]}

de Faria, P. N. ^{[1
]}

Barioni, A. ^{[1
]}

Pires, K. C. C. ^{[1
]}

Morcelle, V. ^{[1
]}

Pampa Condori, R. ^{[1
]}

Morais, M. C. ^{[1
]}

Leistenschneider, E. ^{[1
]}

Lima, C. E. F. ^{[1
]}

Zamora, J. C. ^{[1
]}

Alcantara, J. A. ^{[1
]}

Zagatto, V. ^{[1
]}

Assuncao, M. ^{[3
]}

Shorto, J. M. B. ^{[4
]}

机构：

[1] Univ Sao Paulo, Inst Fis, Dept Fis Nucl, BR-05315970 Sao Paulo, Brazil

[2] ULB, B-1050 Brussels, Belgium

[3] Univ Fed Sao Paulo, Dept Ciencias Exatas & Terra, Sao Paulo, Brazil

[4] Comissao Nacl Energia Nucl, Inst Pesquisas Energet & Nucl IPEN CNEN, Sao Paulo, Brazil

来源：

PHYSICAL REVIEW C | 2012年 / 86卷 / 06期

基金：

巴西圣保罗研究基金会;

关键词：

REACTION CROSS-SECTION; REACTION-RATES; REACTION FLOW; SCATTERING; LIGHT; NUCLEOSYNTHESIS;

D O I：

10.1103/PhysRevC.86.064321

中图分类号：

O57 [原子核物理学、高能物理学];

学科分类号：

070202 ;

摘要：

We present a direct measurement of the low-energy Li-8(p, alpha)He-5 cross section, using a radioactive Li-8 beam impinging on a thick target. With four beam energies, we cover the energy range between E-c.m. = 0.2 and 2.1 MeV. An R-matrix analysis of the data is performed and suggests the existence of two broad overlapping resonances (5/2(+) at E-c.m. = 1.69 MeV and 7/2(+) at E-c.m. = 1.76 MeV). At low energies our data are sensitive to the properties of a subthreshold state (E-x = 16.67 MeV) and of two resonances above threshold. These resonances were observed in previous experiments. The R-matrix fit confirms spin assignments, and provides partial widths. We propose a new Li-8(p, alpha)He-5 reaction rate and briefly discuss its influence in nuclear astrophysics. DOI: 10.1103/PhysRevC.86.064321

引用

页数：10

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