Distillation of scalar exchange by coherent hypernucleus production in antiproton-nucleus collisions

Abstract

The total and angular differential cross sections of the coherent process $\bar p + {}^AZ \to {}^A_\Lambda(Z-1) + \bar{\Lambda}$ are evaluated at the beam momenta $1.5\div20$ GeV/c within the meson exchange model with bound proton and $\Lambda$-hyperon wave functions. It is shown that the shape of the beam momentum dependence of the hypernucleus production cross sections with various discrete $\Lambda$ states is strongly sensitive to the presence of the scalar $\kappa$-meson exchange in the $\bar p p \to \bar\Lambda \Lambda$ amplitude. This can be used as a clean test of the exchange by scalar $\pi K$ correlation in coherent $\bar p A$ reactions.