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arXiv · 2007.10122

Lifetime of the hypertriton

F. Hildenbrand·H. -W. Hammer
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Abstract

We calculate the lifetime of the hypertriton as function of the $Λ$ separation energy $B_Λ$ in an effective field theory with $Λ$ and deuteron degrees of freedom. We also consider the impact of new measurements of the weak decay parameter of the $Λ$. While the sensitivity of the total width to $B_Λ$ is small, the partial widths for decays into individual final states and the experimentally measured ratio $R=Γ_{^3\textrm{He}}/\left(Γ_{^3 \text{He}}+Γ_{pd}\right)$ show a strong dependence. For the standard value $B_Λ=(0.13\pm 0.05)$ MeV, we find $R=0.37\pm 0.05$, which is in good agreement with past experimental studies and theoretical calculations. For the recent STAR value $B_Λ=(0.41\pm0.12\pm0.11)$ MeV, we obtain $R=0.57\pm 0.11$.

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F. Hildenbrand, H. -W. Hammer. 2020-12-10. Lifetime of the hypertriton. https://doi.org/10.1103/physrevc.102.064002

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