Spin-dependent part of interaction cross section and Nijmegen potential

Abstract

Low energypd interaction is considered taking into account the polarization of both particles.The corresponding cross sections are obtained using the Nijmegen nucleon-antinucleon optical potential with shadowing effects taken into account. Double-scattering effects are calculated within the Glauber approach and found to be about 10 ÷ 20%. The cross sections are applied to the analysis of the polarization buildup which is due to the interaction of stored antiprotons with a polarized target. It is shown that, at realistic parameters of a storage ring and a target, the filtering mechanism may provide a noticeable polarization in a time comparable with the beam lifetime. The energy dependence of the polarization rate for deuterium target is similar to that for hydrogen one.However, the time of polarization for deuterium is much smaller than that for hydrogen.

Elastic pbar-d scattering and total pbar-d cross sections

“…Note that a decrease of the absolute values of σ 0 , σ 1 and σ 2 , due to shadowing effects, of comparable magnitude was reported in Ref. [13] in a calculation based on the Nijmegen pN amplitudes [14].…”

“…Nevertheless, for both considered models the magnitude of the spin-dependent cross sections is still comparable or even larger than those for pp [8,43,44]. In this context let us also mention that the values for the polarization degree we obtained are somewhat smaller than those presented in [13], based on the Nijmegen N N partial wave analysis [14] from 1994.…”

“…Indeed corresponding results are certainly desirable, specifically in view of the prospect that a discrimination of existing models of the pN interaction could be feasible on the basis of a comparison with expected data [7]. Antiproton polarization buildup in the context of pd scattering was also studied in a recent work by Salnikov [13], utilizing the results from the Nijmegen pp partial wave analysis [14] from 1994. (Note that an updated partial wave analysis has been presented recently by Zhou and Timmermans [15]).…”

Spin dependence of the pbar-d and pbar-3He interactions

“…Similar effects for pd were reported in Ref. [24] using amplitudes from the Nijmegen pp partial wave analysis [25].…”

Elastic pbar-d scattering and total pbar-d cross sections reexamined

“…Note that pd scattering was also considered in Ref. [9] utilizing, however, the results from the old Nijmegen pp partial-wave analysis [10] from 1994.…”