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تسجيل مستخدم جديدUpdated three-body model of $^6$He $beta$ decay into the $alpha$ + $d$ continuum
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The $beta$-decay process of the $^6$He halo nucleus into the $alpha+d$ continuum is studied in an updated three-body model. The $^6$He nucleus is described as an $alpha+n+n$ system in hyperspherical coordinates on a Lagrange-mesh. The shape and absolute values of the transition probability per time and energy units of new experiments are reproduced with a modified $alpha+d$ potential. The obtained total transition probabilities are $2.48 times 10^{-6}$ s$^{-1}$ for the full energy region and $2.40 times 10^{-6}$ s$^{-1}$ for the cut-off $E>150$ keV. The strong cancellation between the internal and halo parts of the $beta$ decay matrix element is a challenge for future {it ab initio} calculations.
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