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arXiv · 1701.03582

Polarization-transfer observables with polarized beams

Anatoli Plavko
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Abstract

A review is given of our present knowledge of different parametrization of experimental results in inelastic scattering process with polarized proton beams. Spin observables in inelastic proton scattering for a set of lightweight nuclei are studied at intermediate energies in the region of 100-500 MeV. Two important types of DWIA calculations are used in the analysis of experiments. Important spin observables representing the difference functions (P-Ay) and (P-Ay)sigma are examined along with the polarization-transfer (spin-transfer) coefficients D(ij), i.e. D with indices NN, SS, LL, LS and SL, in inelastic scattering of polarized protons. The above indicated value of sigma is the differential cross section. These spin observables are treated in the context of the exchange features of the effective interaction. The linear combinations D(K), D(i) of the complete polarization-transfer observables D(ij) in inelastic proton scattering at intermediate energies are extensively demonstrated. A comparison between systematized, measured and calculated quantities of the combinations D(K) and, partially, sigma 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 T=0 and T=1 unnatural-parity states in some nuclei are discussed. The spin-observable combinations D(Ls) allowed to differentiate reliably the strength of isoscalar and isovector spin-orbit. interactions. The comparison of the experimental and calculated D(K) for the 1+, T = 0 state in 12- C 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. Other observables are also considered for the same purposes.

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Anatoli Plavko. 2017-01-13. Polarization-transfer observables with polarized beams. https://arxiv.org/abs/1701.03582

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