Nuclear Energy Levels of ^31S and ^33Cl

[摘要] The reaction ³²S(³He, α) ³¹S has been used to locate 42levels in ³¹S. For 11 of the first 17 levels ℓ_n-values have beendetermined. The first 6 excited states of ³¹S have been studiedby applying the particle-gamma correlation method of Litherlandand Ferguson (their Method II) to the reaction ³²S(³He, αγ) ³¹S.The resulting spins and parities are: E_X, J^π = 1.25 MeV, 3/2⁺;2.23 MeV, 5/2⁺; 3.08 MeV, 1/2⁺; 3.29 MeV, 5/2⁺, 3/2⁺; 3.35MeV, 7/2, 3/2; 3.44 MeV, 3/2⁺. Mixing and branching ratioshave also been determined. The ground state Q-value for thereaction ³²S(³He, α)³¹S has been measured to be 5.538 ± 0.006MeV. Analysis of the spectra of the reaction ³²S(³He, α)³³Clwhich were obtained as a by-product of the spectra of the reaction³²S(³He, α) ³¹S located levels in ³³Cl at the following excitationenergies: 0, 810 ± 9, (1978 ± 14), 2351 ± 9, 2686 ± 8, 2848 ± 9(a known doublet), 2980 ± 9, and 4119 ± 10 keV. The 2.0 MeVlevel was only weakly populated, and to confirm its existence thereaction ³⁶Ar(p, α)³³Cl has been studied. In this reaction the 2.0MeV level was strongly populated and the measured excitationenergy was 1999 ± 20 keV. The experimental results for³¹S and ³³Cl are compared with their analogs and with nuclear modelpredictions.

[发布机构] University:California Institute of Technology;Department:Physics, Mathematics and Astronomy

[关键词] Physics