Li7+p interaction and excited states of Be8

doi:10.1016/0029-5582(62)90486-8

Nuclear Physics

Volume 36, June–August 1962, Pages 597-614

https://doi.org/10.1016/0029-5582(62)90486-8 Get rights and content

Abstract

The Li⁷+p interaction has been extensively studied and its various products analysed. The results confirm the presence of the well known levels of Be⁸ at 2.9, 17.63 and 18.15 MeV and give clear evidence for the existence of the discussed 7.56 MeV level. Three new levels of Be⁸ have been discovered at the energies 13.91, 17.9 and 18.0 MeV. Widths, angular momenta, parities and isobaric spins of several levels have been determined Some anomalies of the Li⁷+p interaction, previously observed by others, are explained.

References (41)

F. Ajzenberg-Selove et al.
Nuclear Physics
(1959)
F. Ajzenberg-Selove et al.
Ann. Rev. Nucl. Sci.
(1960)
S. Devons et al.S. Devons et al.
J.D. Cockcroft et al.
W.E. Burcham
H.T. Richards
Phys. Rev.
(1941)
L.L. Green et al.
W.F. Hornyak et al.
Rev. Mod. Phys.
(1950)
P. Erdös et al.
Helv. Phys. Acta
(1953)
E.K. Inall et al.
Phil. Mag.
(1953)
E.K. Inall
Phil. Mag.
(1954)
R. Malm et al.
Phys. Rev.
(1953)

E.W. Titterton

Phys. Rev.

(1954)

R.E. Holland et al.

Phys. Rev.

(1955)

E.C. Lavier et al.

Phys. Rev.

(1956)

D.F. Gemmell

Austral. J. Phys.

(1960)

G. Dearnaley et al.

U.K.A.E. report

(Aug. 1960)

S.S. Friedland et al.

Nucleonics

(1960)

N.P. Heydenburg et al.

Phys. Rev.

(1948)

N.P. Heydenburg et al.

Phys. Rev.

(1948)

J.M. Freeman et al.

Nuclear Physics

(1958)

D.R. Inglis

Phys. Rev.

(1948)

W.A. Fowler et al.

Phys. Rev.

(1949)

Cited by (3)

Cross-section measurement for the 7Li(p,α)4He reaction at proton energies 0.6 – 2 MeV
2022, Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms
Citation Excerpt :
Knowledge about the 7Li(p,α)4He reaction cross section is certainly important for nuclear data evaluation. However, the existing cross-section datasets in the literature are unfortunately inadequate and discrepant in many cases [5–15]. Fig. 1 shows the data of 7Li(p,α)4He reaction cross section, and Fig. 2 shows the data of differential cross-section of this reaction.
Reliable data on the ⁷Li(p,α)⁴He reaction cross section are important for many applications, including fusion and accelerator neutron sources with a lithium target. Existing in the literature cross-section datasets in the literature are unfortunately inadequate and discrepant in many cases. In this study, the ⁷Li(p,α)⁴He reaction cross section is determined for proton energies E = 0.6–2 MeV. The experimental data are compared with the data from literature.
The polarized proton capture reaction 7Li(d, γ)8Be in the energy range from 380 to 960 keV
1977, Nuclear Physics, Section A
The polarized proton capture in ⁷Li was used to study the reaction mechanism and to obtain spectroscopic information on the ⁸Be nucleus. Gamma-ray angular distributions of the analyzing power were measured as a function of proton energy from E_p = 380–960 keV with three Ge(Li) detectors simultaneously. The excitation functions of the cross section and the analyzing power are strongly energy dependent. The data were analyzed unambiguously and represented by three R-matrix elements, two M1 and one E1. The energy dependence of the two M1 matrix elements agrees with the well-known two 1⁺ resonances at E_x = 17.642 and 18.157 MeV. The energy dependence of the E1 matrix element shows a smooth background presumably caused by a direct-capture mechanism, and furthermore, a resonant contribution, which is a significant suggestion of a new 1⁻ state in the ⁸Be system at E_x = 17.70 MeV with a width of Γ_p = 180 keV.
Reactions 7Li + n, 7Li + p and excited states of the A = 8 system
1972, Nuclear Physics, Section A
Integral cross sections of the analogous reactions ⁷Li(n, n₁)⁷Li, ⁷Li(p,p₁)⁷Li and ⁷Li (p,n₁)⁷Be were obtained for neutron energies between 1.0 and 9.0 MeV and for proton energies between 2.0 and 6.0 MeV by observing the γ-radiation emitted from the final states with Ge(Li) detectors. In addition some (n,n₁) cross sections on ⁷Li were measured for neutron energies around 20 MeV. The (n, n₁) excitation function was analyzed in the framework of resonance theory together with existing information on the elastic scattering of neutrons from ⁷Li. Two states in ⁸Li with the parameters $E_{x} (^{8} Li) = 5.53 MeV$ , Γ = 0.66 MeV and $E_{x} (^{8} Li) = 6.40 MeV$ , Γ = 1.14 MeV were clearly observed. The results for ⁷Li+p and the question of isospin mixing in ⁸Be are discussed in a qualitative manner.

View full text

Article preview

Nuclear Physics

Abstract

References (41)

Nuclear Physics

Ann. Rev. Nucl. Sci.

Phys. Rev.

Rev. Mod. Phys.

Helv. Phys. Acta

Phil. Mag.

Phil. Mag.

Phys. Rev.

Phys. Rev.

Phys. Rev.

Phys. Rev.

Austral. J. Phys.

U.K.A.E. report

Nucleonics

Phys. Rev.

Phys. Rev.

Nuclear Physics

Phys. Rev.

Phys. Rev.

Cited by (3)

Cross-section measurement for the <sup>7</sup>Li(p,α)<sup>4</sup>He reaction at proton energies 0.6 – 2 MeV

The polarized proton capture reaction <sup>7</sup>Li(d, γ)<sup>8</sup>Be in the energy range from 380 to 960 keV

Reactions <sup>7</sup>Li + n, <sup>7</sup>Li + p and excited states of the A = 8 system