Two-step processes in the 40Ca(α, 3He)41Ca reaction
Abstract
The 40Ca(α, 3He) reaction has been studied at 36 MeV incident energy. About fifty levels have been observed up to 7.1 MeV excitation energy and angular distributions were measured from 6–60° using a split-pole spectrometer. A local zero-range DWBA analysis has been carried out, and the deduced l-assignments and spectroscopic factors are compared with those obtained from previous neutron stripping experiments. Core-excited states in 41Ca with a [3− ⊗ f7,2], [2+ ⊗ f7,2] and [5− ⊗ f7,2] component previously observed in inelastic scattering experiments, are selectively excited by the (α, 3He) reaction. Their angular distributions are compared with coupled-reaction-channel calculations, assuming a pure two-step reaction mechanism. The agreement between theory and experiment may be considered as rather satisfactory for a number of levels. In particular the levels and the high-spin states with are successfully described within the framework of the weak-coupling model.
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- lifetimes γm or widths Λ,
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Investigation of single-particle strength distributions in a high-resolution <sup>40</sup>Ca(ovarr|d,p) study at E<inf>d</inf> = 20 MeV
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Direct transfer and two-step processes in the <sup>42</sup>Ca(α, <sup>3</sup>He)<sup>43</sup>Ca reaction
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