Microscopic calculation of antiproton-nucleus elastic scattering

doi:10.1016/0375-9474(86)90292-7

Nuclear Physics A

Volume 451, Issue 4, 7 April 1986, Pages 562-580

https://doi.org/10.1016/0375-9474(86)90292-7 Get rights and content

Abstract

The antiproton-nucleon T-matrix of the Dover-Richard interaction is fitted by a linear combination of simple functions. The one-pion exchange potential is included explicitly, and the remainder is approximated by either Gauss or Yukawa functions. Including a linear energy dependence improves the fit significantly. The optical potential is then obtained by folding with the nuclear density, taking into account the size of the antiproton. When an energy or relative momentum-squared dependence of the central part of the T-matrix is included, the corresponding gradient operators lead to an optical potential containing unusual terms. This corresponds to a generalization of Skyrme-like forces to finite range and to the inclusion of an imaginary effective mass. For scattering the latter term is equivalent to a definite energy-dependent optical potential. Elastic scattering cross sections for 300 and 600 MeV/c antiprotons on ¹²C, ⁴⁰Ca and ²⁰⁸Pb are computed using the KMT procedure for the optical potentials resulting from the various T-matrix approximations. Comparisons with available experimental values give $solχ^{2} N$ values typically around 4. The different choices of functions give rather similar results.

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Microscopic calculation of antiproton-nucleus elastic scattering

Abstract

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