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arXiv · 2207.07360

SS-HORSE Extension of the No-Core Shell Model: Application to Resonances in $^7{\mathrm He}$

I. A. Mazur·I. J. Shin·Y. Kim·A. I. Mazur·A. M. Shirokov·P. Maris·J. P. Vary
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Abstract

Theoretical ab initio studies of resonances in the unbound ${\rm^{7}He}$ nucleus are presented. We perform no-core shell model calculations with $NN$ interactions Daejeon16 and JISP16 and utilize the SS-HORSE method to calculate the $S$ matrix for two-body channels $n{-}{\rm^{6}He}$ and $n{-}{\rm^{6}He^{*}}$ with ${\rm^{6}He}$ respectively in the ground and excited $2^{+}$ states as well as for the four-body democratic decay channel ${{\rm^{4}He}+n+n+n}$. The resonant energies and widths areobtained by numerical location of the $S$-matrix poles. We describe all experimentally known ${\rm^{7}He}$ resonances and suggest an interpretation of an observed wide resonance of unknown spin-parity.

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I. A. Mazur, I. J. Shin, Y. Kim, A. I. Mazur, A. M. Shirokov, P. Maris, J. P. Vary. 2022-07-15. SS-HORSE Extension of the No-Core Shell Model: Application to Resonances in $^7{\mathrm He}$. https://doi.org/10.1103/physrevc.106.064320

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