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Probing hadronic formation times with antiprotons in p+A reactions at AGS energies

W. Cassing·E. L. Bratkovskaya·O. Hansen
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Abstract

The production of antiprotons in $p+A$ reactions is calculated in a microscopic transport approach employing hadronic and string degrees of freedom (HSD). It is found that the abundancies of antiprotons as observed by the E910 Collaboration in $p+A$ reactions at 12.3 GeV/c as well as 17.5 GeV/c can approximately be described on the basis of primary proton-nucleon and secondary meson-baryon production channels for all targets. The transport calculations demonstrate that the antiproton rapidity distributions for heavy targets are sensitive to the $\bar{p}$ (or hadron) formation time in the nuclear medium. Within our analysis the data from the E910 Collaboration are reasonably described with a formation time of $ 0.4-0.8$ fm/c in the hadron rest frame.

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W. Cassing, E. L. Bratkovskaya, O. Hansen. 2002-03-12. Probing hadronic formation times with antiprotons in p+A reactions at AGS energies. https://doi.org/10.1016/s0375-9474(02)00919-3

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