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arXiv · 0711.1997

s-Wave Approximation for Asymmetry in Nonmesonic Decay of Finite Hypernuclei

Cesar Barbero·Alfredo P. Galeao·F. Krmpotic
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Abstract

We establish the bridge between the commonly used Nabetani-Ogaito-Sato-Kishimoto (NOSK) formula for the asymmetry parameter $a_Λ$ in the $\vecΛp \to np$ emission of polarized hypernuclei, and the shell model (SM) formalism for finite hypernuclei. We demonstrate that the s-wave approximation leads to a SM formula for $a_Λ$ that is as simple as the NOSK one, and that reproduces the exact results for $^5_Λ$He and $^{12}_Λ$C better than initially expected. The simplicity achieved here is indeed remarkable. The new formalism makes the theoretical evaluation of $a_Λ$ more transparent, and explains clearly why the one-meson exchange model is unable to account for the experimental data of $^5_Λ$He.

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Cesar Barbero, Alfredo P. Galeao, F. Krmpotic. 2007-11-13. s-Wave Approximation for Asymmetry in Nonmesonic Decay of Finite Hypernuclei. https://doi.org/10.1103/physrevc.76.054321

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