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تسجيل مستخدم جديدStudy of nuclear correlation effects via 12C(p,n)12N(g.s.,1+) at 296 MeV
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We report measurements of the cross section and a complete set of polarization observables for the Gamow--Teller ${}^{12}{rm C}(vec{p},vec{n}){}^{12}{rm N}({rm g.s.},1^+)$ reaction at a bombarding energy of 296 MeV. The data are compared with distorted wave impulse approximation calculations employing transition form factors normalized to reproduce the observed beta-decay $ft$ value. The cross section is significantly under-predicted by the calculations at momentum transfers $q gtrsim $ 0.5 ${rm fm^{-1}}$. The discrepancy is partly resolved by considering the non-locality of the nuclear mean field. However, the calculations still under-predict the cross section at large momentum transfers of $q$ $simeq$ 1.6 ${rm fm^{-1}}$. We also performed calculations employing random phase approximation response functions and found that the observed enhancement can be attributed in part to pionic correlations in nuclei.
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Differential cross sections and complete sets of polarization observables are presented for the Gamow-Teller $^{12}{rm C}(vec{p},vec{n})^{12}{rm N}({rm g.s.},1^+)$ reaction at a bombarding energy of 296 MeV with momentum transfers $q$ of 0.1 to $2.2{
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