Relativistic effects on polarization transfer observables for quasielastic proton-nucleus scattering

Journal Article · Sat Jan 01 04:00:00 EST 1994 · Physical Review, C (Nuclear Physics); (United States)

DOI:https://doi.org/10.1103/PhysRevC.49.391· OSTI ID:5407135

Hillhouse, G C; De Kock, P R ^[1]

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1. University of Stellenbosch, Stellenbosch 7600 (South Africa) National Accelerator Centre, Faure 7131 (South Africa)

Within the relativistic plane-wave impulse approximation, the sensitivity of complete sets of quasielastic proton-nucleus spin observables is investigated with respect to relativistic effects, the importance of exchange contributions to the [ital NN] amplitudes, the form of the [pi][ital N] vertex, and spin-orbit distortions. Calculations are performed at laboratory energies ranging from 135 to 500 MeV and for target nuclei ranging from [sup 12]C to [sup 208]Pb at a fairly large fixed momentum transfer of 1.97 fm[sup [minus]1]. Of all the spin observables, only [ital A][sub [ital y]] exhibits a clear relativistic effect at the highest energy, as has been previously found. However, at the lower energies (200 MeV and below) the relativistic effect shifts to two other polarization transfer observables, mainly [ital D][sub [ital s][prime][ital s]] and to a lesser extent [ital D][sub [ital l][prime][ital s]]. In addition, it is found that [ital D][sub [ital n][prime][ital n]] is extremely sensitive to the pseudoscalar versus pseudovector ambiguity of the [pi][ital N] vertex, whereas [ital D][sub [ital s][prime][ital l]] and [ital D][sub [ital l][prime][ital l]] are sensitive to exchange contributions to the [ital NN] amplitudes. Compared to the latter, the effects of spin-orbit distortion are not insignificantly small and had to be corrected for. This investigation stresses the urgent need for measurements of the quasielastic spin observables at these low energies.

• OSTI ID: 5407135
• Journal Information: Physical Review, C (Nuclear Physics); (United States), Journal Name: Physical Review, C (Nuclear Physics); (United States) Vol. 49:1; ISSN 0556-2813; ISSN PRVCAN
• Country of Publication: United States
• Language: English

Related Subjects

663300 -- Nuclear Reactions & Scattering
General-- (1992-)
663430* -- Nucleon-Induced Reactions & Scattering-- (1992-)
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ANALYZING POWER
BARYON REACTIONS
BEAMS
CHARGED-PARTICLE REACTIONS
DIRECT REACTIONS
ENERGY RANGE
HADRON REACTIONS
HADRON-HADRON INTERACTIONS
IMPULSE APPROXIMATION
INTERACTIONS
MESON-BARYON INTERACTIONS
MESON-NUCLEON INTERACTIONS
MEV RANGE
MEV RANGE 100-1000
NUCLEAR REACTIONS
NUCLEON REACTIONS
PARTICLE INTERACTIONS
PION-NUCLEON INTERACTIONS
POLARIZATION
POLARIZED BEAMS
PROTON REACTIONS
QUASI-ELASTIC SCATTERING
QUASI-FREE REACTIONS
RELATIVISTIC RANGE
SCATTERING