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Reanalysis of antiproton production in proton-nucleus and nucleus-nucleus reactions at subthreshold energies

A. Sibirtsev·W. Cassing·G. I. Lykasov·M. V. Rzjanin
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Abstract

We reanalyse the production of $p\bar{p}$ pairs in proton-nucleus and nucleus-nucleus collisions employing novel elementary cross sections for baryon-baryon and pion-baryon production channels based on a boson-exchange model. In contrast to previous transport studies performed in the literature the secondary pion induced channel is found to be most important in both p+A and A+A collisions at subthreshold energies. A detailed comparison with the experimental data available indicates that sizeable attractive $\bar{p}$ potentials in the order of - 100 to - 150 MeV at normal nuclear matter density are needed to reproduce the size and shape of the experimental spectra.

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A. Sibirtsev, W. Cassing, G. I. Lykasov, M. V. Rzjanin. 1997-10-20. Reanalysis of antiproton production in proton-nucleus and nucleus-nucleus reactions at subthreshold energies. https://doi.org/10.1016/s0375-9474(97)00809-9

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