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Physical Review C

Scattering lengths for p−3He elastic scattering from an effective-range phase shift analysis

Elizabeth George, L. D. Knutson

Published Feb 4, 2003• 10 citations
Publisher

Abstract

We have extended an earlier phase-shift analysis of $p{\ensuremath{-}}^{3}\mathrm{He}$ scattering data by including additional low-energy measurements in the dataset. The $p{\ensuremath{-}}^{3}\mathrm{He}$ zero-energy scattering lengths obtained from this analysis depend sensitively on a group of cross section and analyzing power measurements at proton energies below 1 MeV. When this group of measurements is included in the dataset, two possible phase-shift solutions are found. The first solution yields a singlet scattering length of ${a}_{s}=15.1\mathrm{fm}$ and a triplet scattering length of ${a}_{t}=7.9\mathrm{fm},$ while the second solution yields values of ${a}_{s}=7.2\mathrm{fm}$ and ${a}_{t}=10.4\mathrm{fm}.$ Without this group of measurements, the best-fit scattering lengths are ${a}_{s}=10.3\mathrm{fm}$ and ${a}_{t}=8.2\mathrm{fm}.$ We believe that the scattering lengths are currently not well determined experimentally and that additional low-energy $p{\ensuremath{-}}^{3}\mathrm{He}$ data are needed in order to clarify the situation.

DOI
10.1103/physrevc.67.027001

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