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arXiv · 1512.01535

On Quasibound N* Nuclei

N. G. Kelkar·D. Bedoya Fierro·P. Moskal
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Abstract

The possibility for the existence of unstable bound states of the S11 nucleon resonance N$^*$(1535) and nuclei is investigated. These quasibound states are speculated to be closely related to the existence of the quasibound states of the eta mesons and nuclei. Within a simple model for the N N$^*$ interaction involving a pion and eta meson exchange, N$^*$-nucleus potentials for N*-$^3$He and N*-$^{24}$Mg are evaluated and found to be of a Woods-Saxon like form which supports two to three bound states. In case of N*-$^3$He, one state bound by only a few keV and another by 4 MeV is found. The results are however quite sensitive to the N N$^*$ $\pi$ and N N$^*$ $\eta$ vertex parameters. A rough estimate of the width of these states, based on the mean free path of the exchanged mesons in the nuclei leads to very broad states with $\Gamma \sim$ 80 and 110 MeV for N*-$^3$He and N*-$^{24}$Mg respectively.

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N. G. Kelkar, D. Bedoya Fierro, P. Moskal. 2015-12-04. On Quasibound N* Nuclei. https://doi.org/10.5506/aphyspolb.47.299

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