Comments on $\bf{η'}$ nuclei and on the $Λ$ binding energy of the hypertriton

Avraham Gal

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arXiv · 2610.40173

Comments on $\bf{η'}$ nuclei and on the $Λ$ binding energy of the hypertriton

Avraham Gal

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Abstract

I briefly discuss two apparent puzzles: (i) is the observation of $η'$(958) bound states in $^{11}$C at GSI [1] compatible with a nearly vanishing real part of $η'N$ scattering length [2]? and (ii) is the $Λ$ binding energy of the hypertriton (${{_Λ}^3}$H), the lightest particle-stable hypernucleus, very small (63$^{+38}_{-31}$ keV, J-PARC E73 [3]) or very large (523$\pm$76 keV, MAMI [4])? Here, I suggest that MAMI's observed weak-decay pion momentum peak originates from ${{_Λ}^7}$He, not from ${{_Λ}^3}$H \cite{Gal26}.

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Avraham Gal. 2026-10-29. Comments on $\bf{η'}$ nuclei and on the $Λ$ binding energy of the hypertriton. https://arxiv.org/abs/2610.40173

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