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arXiv · 1507.00468

Unnatural-parity (p,p') reactions in a factorized impulse-approximation model for polarization transfer and spin responses

A. V. Plavko·M. S. Onegin·V. I. Kudriashov
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Abstract

Linear combinations $D_K$ of the complete polarization-transfer observables, Dij, in the (p,p') reaction at intermediate energies are demonstrated. A comparison between systematized measured and calculated values of the combinations $D_K$ for the $1^+$ (T = 0 and T = 1) levels in $^{12}$C, for the $4^-$ (T = 0 and T = 1) states in $^{16}$O, and for the $6^-$ (T = 0 and T = 1) levels in $^{28}$Si are reported. Particularities in angular distributions of transverse- and longitudinal-spin-transfer probabilities, $D_K$, for the T = 0 and T = 1 unnatural-parity states in the indicated nuclei are discussed. The spin-observable combinations Dls allowed to differentiate reliably the strength of the isoscalar and isovector spin-orbit interactions. The comparison of experimental $D_K$ and calculated $D_K$ with the use of zero-range treatment (LEA code) and exact finite-range calculations (DWBA-91 program) made it possible to identify the role of exchange contributions.

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A. V. Plavko, M. S. Onegin, V. I. Kudriashov. 2015-07-02. Unnatural-parity (p,p') reactions in a factorized impulse-approximation model for polarization transfer and spin responses. https://arxiv.org/abs/1507.00468

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