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arXiv · 1703.02073

Coherent Hypernucleus Production in Antiproton-Nucleus Annihilation Reactions as a Probe for $κ$ meson Exchange

A. B. Larionov·H. Lenske
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Abstract

The hypernucleus production reaction $\bar p + {}^AZ \to {}^A_Λ(Z-1) + \barΛ$ in the beam momentum range 1.5-20 GeV/c is addressed theoretically as a coherent process. The calculations are based on a covariant $t$-channel meson exchange model for the elementary $\bar p p \to \barΛΛ$ annihilation amplitude with parameters fixed by comparison with empirical data. Besides pseudo-scalar $K$ and vector $K^*$ mesons we also account for correlated $πK$ contributions, modelled by the scalar $K^*_0(800)$ or $κ$ meson. Initial and final state nuclear interactions are taken into account in eikonal approximation. The bound baryon wave functions are obtained self-consistently in a covariant mean-field approach. It is shown that the hypernucleus production cross sections populating discrete states are dominated by the vector and scalar interaction channels. The pronounced sensitivity on the scalar $κ$ meson exchange contributions indicates that these reactions are well suited as a probe for correlated $πK$ exchange in the scalar $κ/K^*_0$ interaction channel.

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A. B. Larionov, H. Lenske. 2017-03-12. Coherent Hypernucleus Production in Antiproton-Nucleus Annihilation Reactions as a Probe for $κ$ meson Exchange. https://arxiv.org/abs/1703.02073

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