Title:
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Exchange effects in (p,pd) and similar reactions
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The differential cross-sections for the Li[6] (p,pd), Li[7] (p,pd) and Li[7] (p,pt) reactions have been calculated in the plane wave Born approximation using antisymmetrized harmonic oscillator cluster model wavefunctions. In all three reactions the target exchange terms, resulting from antisymmetrization of the wavefunction with respect to the target nucleons, were computed, and for the Li[6] (p,pd) reaction the incident-target exchange terms, resulting from antisymmetrization with respect to the incident proton, were included. Using an (alpha+t) cluster configuration for Li[7] and (alpha+d) for Li a range of wavefunction parameters, corresponding to different degrees of clustering and giving an r.m.s. radius equal to the experimental value obtained from elastic electron scattering, was obtained by fixing the alpha cluster parameter and varying the remaining cluster parameter together with the cluster separation. The calculation of r.m.s. radii using antisymmetrized cluster wavefunctions has been described. The behaviour of the exchange terms with both energy and clustering has been examined. For the Li[6] (p,pd) and Li[7] (p,pd) reactions, it was found that the inclusion of target exchange did not appreciably alter the shape of the cross-section; while for the Li[7] (p,pt) reaction, the shape of the cross-section, calculated with target exchange terms, was found to depend critically on both energy and clustering. The inclusion of incident-target exchange terms in the Li[6] (p,pd) reaction was found to affect the shape of the cross-section only at energies below 100 MeV and for weakly clustered nuclei.
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