arXiv 1503.057922015-03-19nucl-exnucl-th

Broad resonances and beta-decay

K. Riisager, H. O. U. Fynbo, S. Hyldegaard, A. S. Jensen

备注：: 27 pages, 5 figures
发表信息：: Nuclear Physics A940 (2015) 119-137
DOI：: 10.1016/j.nuclphysa.2015.04.003

英文摘要：

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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