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arXiv · 2609.32986

$ \bar K^0 d $ Bound State and Correlation Function

M. Bayar·P. Encarnación·A. Feijoo·E. Oset
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Abstract

We study the $\bar{K}^0d$ system using a new formulation of the fixed-center approximation that preserves elastic unitarity. The resulting scattering amplitude predicts a bound state below threshold, which can be interpreted as a $Λ(1380)N$ configuration complementary to the $K^-pp$ state associated with the higher $Λ(1405)$ pole. The interaction is attractive, with scattering parameters of the same order as recent $K^-d$ determinations. We further calculate the $\bar{K}^0d$ correlation function, which exhibits a characteristic structure associated with the bound state and provides a Coulomb-free observable that can be tested in future ALICE measurements. Results obtained with two different $\bar{K}N$ models are very similar, indicating the robustness of the predictions against the choice of the underlying interaction.

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M. Bayar, P. Encarnación, A. Feijoo, E. Oset. 2026-09-26. $ \bar K^0 d $ Bound State and Correlation Function. https://arxiv.org/abs/2609.32986

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