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arXiv · 2407.11136

Spin correlation in two-proton emission from $^6$Be

Tomohiro Oishi
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Abstract

This paper presents a theoretical evaluation of spin correlation in the two-proton ($2p$) radioactive emission. The three-body model of $^{6}$Be with the proton-proton interaction, which is adjusted to reproduce the experimental energy release, is utilized. Time-dependent calculation is performed to compute the coupled-spin state of the emitted two protons. The spin-correlation function $S$ as the Clauser-Horne-Shimony-Holt (CHSH) indicator is evaluated as $|S| \cong 2.65$. Namely, the $2p$-spin correlation beyond the limit of local-hidden-variable (LHV) theory is suggested. This correlation is sensitive to the proton-proton interaction. The short-lived (broad-width) $2p$~state has the weaker spin correlation. In parallel, the core-proton interactions do not harm this correlation during the time-dependent decaying process. The CHSH measurement can be a novel probe into the effective nuclear interaction inside finite systems. Two-proton emitters can provide a testing field for identical-particle entanglement.

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Tomohiro Oishi. 2024-07-15. Spin correlation in two-proton emission from $^6$Be. https://arxiv.org/abs/2407.11136

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