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arXiv · 2501.02826

In-medium $\Lambda N$ interactions with leading order covariant chiral hyperon/nucleon-nucleon forces

Ru-You Zheng·Zhi-Wei Liu·Li-Sheng Geng·Jin-Niu Hu·Sibo Wang
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Abstract

In-medium $\Lambda N$ interactions are crucial in hypernuclei and neutron star physics. In this work, we study the in-medium $\Lambda N$ interaction within the relativistic Brueckner-Hartree-Fock (RBHF) framework, employing the leading-order covariant chiral hyperon/nucleon-nucleon forces for the first time. We demonstrate that a consistent description of both the experimental cross-section data and the `empirical value' of the $\Lambda$ single-particle potential can be achieved. This contrasts with the majority of studies in the non-relativistic framework, where higher-order two-body chiral forces are typically required. This study offers a new perspective on the in-medium $\Lambda N$ interactions, urgently needed in relativistic \textit{ab initio} hypernuclear physics studies.

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Ru-You Zheng, Zhi-Wei Liu, Li-Sheng Geng, Jin-Niu Hu, Sibo Wang. 2025-01-06. In-medium $\Lambda N$ interactions with leading order covariant chiral hyperon/nucleon-nucleon forces. https://arxiv.org/abs/2501.02826

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