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arXiv · 2309.14711

Probing the existence of \eta^3He mesic nucleus with a few-body approach

Qian Wu·Gang Xie·Xurong Chen
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Abstract

Motivated by the two recent observations in the WASA-at-COSY detector, we investigate the $\eta^3$He nucleus with the $\eta NNN$ few body method. We construct the effective $s$-wave energy dependent $\eta N$ potential which reproduce the $\eta N$ subthreshold scattering amplitude in the 2005 Green-Wycech model. It gives the $\eta$ separation energy and decay width of 0.19 MeV and 1.71 MeV, respectively. We also construct various sets of effective $s$-wave energy independent $\eta N$ potentials where the corresponding complex scattering lengths (a) are within the range given in most theoretical models. We obtain the bound $\eta^3$He nucleus with decay width of about 5 MeV when a is (1.0 fm, 0.3 fm), and of about 10 MeV when a is (1.0 fm, 0.5 fm).

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Qian Wu, Gang Xie, Xurong Chen. 2023-09-26. Probing the existence of \eta^3He mesic nucleus with a few-body approach. https://doi.org/10.1016/j.physletb.2024.138502

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