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arXiv · 1503.05792

Broad resonances and beta-decay

K. Riisager·H. O. U. Fynbo·S. Hyldegaard·A. S. Jensen
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Abstract

Beta-decay into broad resonances gives a distorted lineshape in the observed energy spectrum. Part of the distortion arises from the phase space factor, but we show that the beta-decay matrix element may also contribute. Based on a schematic model for p-wave continuum neutron states it is argued that beta-decay directly to the continuum should be considered as a possible contributing mechanism in many decays close to the driplines. The signatures in R-matrix fits for such decays directly to continuum states are discussed and illustrated through an analysis of the beta-decay of $^8$B into $2^+$ states in $^8$Be.

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K. Riisager, H. O. U. Fynbo, S. Hyldegaard, A. S. Jensen. 2015-03-19. Broad resonances and beta-decay. https://doi.org/10.1016/j.nuclphysa.2015.04.003

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