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Annihilation of antiprotons on nuclear targets at low energies: a simple analysis

A. Bianconi·G. Bonomi·E. Lodi Rizzini·L. Venturelli·A. Zenoni
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Abstract

We set up a plane wave impulse approximation (PWIA) formalism for the analysis of the annihilation cross sections of antinucleons on nuclear targets at very low momenta (below 100 MeV/c), where semiclassical approximations can't be applied. Since, as we test here, PWIA fails in reproducing the unexpected ``inversion'' behavior of the $\bar{p}p$ and $\bar{p}-$nucleus annihilation cross sections found in a recent experiment\cite{obe1,obe2} we discuss some further possibilities, with a special attention to the optical potential model.

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A. Bianconi, G. Bonomi, E. Lodi Rizzini, L. Venturelli, A. Zenoni. 1999-10-12. Annihilation of antiprotons on nuclear targets at low energies: a simple analysis. https://arxiv.org/abs/nucl-th/9910031

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