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arXiv · 1712.07982

Eta-mesic nuclei

A. Cieply·J. Mares·M. Schaefer·N. Barnea·B. Bazak·E. Friedman·A. Gal
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Abstract

In this contribution we report on theoretical studies of $\eta$ nuclear quasi-bound states in few- and many-body systems performed recently by the Jerusalem-Prague Collaboration [1-5]. Underlying energy-dependent $\eta N$ interactions are derived from coupled-channel models that incorporate the $N^*(1535)$ resonance. The role of self-consistent treatment of the strong energy dependence of subthreshold $\eta N$ amplitudes is discussed. Quite large downward energy shift together with rapid decrease of the $\eta N$ amplitudes below threshold result in relatively small binding energies and widths of the calculated $\eta$ nuclear bound states. We argue that the subthreshold behavior of $\eta N$ scattering amplitudes is crucial to conclude whether $\eta$ nuclear states exist, in which nuclei the $\eta$ meson could be bound and if the corresponding widths are small enough to allow detection of these $\eta$ nuclear states in experiment.

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A. Cieply, J. Mares, M. Schaefer, N. Barnea, B. Bazak, E. Friedman, A. Gal. 2017-12-21. Eta-mesic nuclei. https://arxiv.org/abs/1712.07982

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