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Proton-helium elastic scattering: a possible high-energy polarimeter at RHIC-BNL

C. Bourrely·J. Soffer
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Abstract

We examine a suggestion to use ${p-} ^4{He}$ elastic scattering, as an absolute polarimeter for high-energy polarized proton beams, by means of a Coulomb-Nuclear Interference effect for the single-spin asymmetry $A_N(t)$, around the diffractive minimum of the differential cross section $|t|\sim 0.21 GeV^2$. Although this reaction has a fairly simple dynamical structure, our theoretical uncertainties and the present experimental inaccuracy of the differential cross section in this $t$ region, allows one to generate dramatic effects for $A_N(t)$, which will be discussed.

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C. Bourrely, J. Soffer. 1998-09-17. Proton-helium elastic scattering: a possible high-energy polarimeter at RHIC-BNL. https://doi.org/10.1016/s0370-2693(98)01272-6

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