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arXiv · 2211.01693

Study on $Λnn$ Bound State and Resonance

Thiri Yadanar Htun·Yupeng Yan
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Abstract

We perform the ab initio no-core shell model (NCSM) calculation to investigate the bound state problem of the three-body $Λnn$ system in chiral next-to-next-to-leading-order NN and chiral leading-order YN interactions. The calculations show that no $Λnn$ bound state exists, but predict a low-lying $Λnn$ resonant state near the threshold with the energy of $E_r= 0.124$ MeV and the width of about $Γ=1.161$ MeV. In searching for $Λnn$ resonances, we extend the NCSM calculation to the continuum state by employing the J-matrix formalism in the scattering theory with the hyperspherical oscillator basis.

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Thiri Yadanar Htun, Yupeng Yan. 2022-11-03. Study on $Λnn$ Bound State and Resonance. https://doi.org/10.1103/physrevc.105.064001

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