Large asymmetry in the strongest β-transition for A=9

doi:10.1016/j.physletb.2003.09.073

Physics Letters B

Volume 576, Issues 1–2, 4 December 2003, Pages 55-61

https://doi.org/10.1016/j.physletb.2003.09.073 Get rights and content

Abstract

A new measurement of the β-decay of ⁹Li has clarified the feeding to the highest accessible states in ⁹Be. It is found that the β-decay mainly populates the 11.8 MeV state, whose spin is determined as 5/2⁻. The extracted B_GT value of 5.3(0.9) is a factor 4.4(1.0) larger than that of the mirror transition from ⁹C. A theoretical explanation of such a pronounced β-decay asymmetry is presently lacking.

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Acknowledgements

One of us (Y.P.) thanks the Spanish Ministery of Science and Technology for the 4-year grant assigned to the project AEN1999-1046-C02-01. The work was supported by the European Union Fifth Framework Programme “Improving Human Potential, Access to Research Infrastructure”.

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Physics Letters B

Abstract

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Acknowledgements

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Cited by (34)

<sup>9</sup>Li and <sup>8</sup>He decays in GEANT4

The strength of beta-decays to the continuum

Recent experimental progress in nuclear halo structure studies

Study of β-delayed 3-body and 5-body breakup channels observed in the decay of <sup>11</sup>Li

Nuclear structure at the proton drip line: Advances with nuclear decay studies

Low-lying resonance states in the <sup>9</sup>Be continuum