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DOE OSTI · 21499189

Deducing spectroscopic factors from wave-function asymptotics

Capel, P·Danielewicz, P·Nunes, F M
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Abstract

In a coupled-channel model, we explore the effects of coupling between configurations on the radial behavior of the wave function and, in particular, on the spectroscopic factor (SF) and the asymptotic normalization coefficient (ANC). We evaluate the extraction of a SF from the ratio of the ANC of the coupled-channel model to that of a single-particle approximation of the wave function. We perform this study within a core+n collective model, which includes two states of the core that connect by a rotational coupling. To get additional insights, we also use a simplified model that takes a {delta} function for the coupling potential. Calculations are performed for {sup 11}Be. Fair agreement is obtained between the SF inferred from the single-particle approximation and the one obtained within the coupled-channel models. Significant discrepancies are observed only for large coupling strength and/or large admixture, that is, a small SF. This suggests that reliable SFs can be deduced from the wave-function asymptotics when the structure is dominated by one configuration, that is, for a large SF.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICSALKALINE EARTH ISOTOPESAPPROXIMATIONSASYMPTOTIC SOLUTIONSBERYLLIUM 11BERYLLIUM ISOTOPESBETA DECAY RADIOISOTOPESBETA-MINUS DECAY RADIOISOTOPESCALCULATION METHODSCOLLECTIVE MODELCOUPLED CHANNEL THEORYCOUPLINGDELTA FUNCTIONDIMENSIONLESS NUMBERSEVEN-ODD NUCLEIEXTRACTIONFUNCTIONSISOTOPESLIGHT NUCLEIMATHEMATICAL MODELSMATHEMATICAL SOLUTIONSNUCLEAR MODELSNUCLEIRADIOISOTOPESSECONDS LIVING RADIOISOTOPESSEPARATION PROCESSESSPECTROSCOPIC FACTORSWAVE FUNCTIONS

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Capel, P, Danielewicz, P, Nunes, F M. 2010-11-15. Deducing spectroscopic factors from wave-function asymptotics. https://doi.org/10.1103/physrevc.82.054612

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