Transport analysis of K+ production in proton-nucleus reactions

Abstract

The production of $K^{+}$ mesons in proton-nucleus collisions from 1.0 to 2.3 GeV is analyzed with respect to one-step nucleon-nucleon $(NN\to NY{K}^{+}$) and two-step $\hat{I}”$-nucleon $(\hat{I}”N\to K^{+}YN$) or pion-nucleon $(\ddot{I}€N\to K^{+}Y$) production channels on the basis of a coupled-channel transport approach (CBUU) including the kaon final-state-interactions (FSI). Momentum-dependent potentials for the nucleon, hyperon and kaon in the final state are included as well as $K^{+}$ elastic rescattering in the target nucleus. The transport calculations are compared to the experimental $K^{+}$ spectra taken at COSY-Jülich. Our systematic analysis of $K^{+}$ spectra from ${}^{12}C$, ${}^{63}Cu$, ${}^{107}Ag$ and ${}^{197}Au$ targets as well as their momentum differential ratios gives a repulsive $K^{+}$ potential of $20\pm 5$ MeV at normal nuclear matter density.

7 pages, 5 figures, submitted to Eur. Phys. J. A