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arXiv · 1206.0046

Ab initio calculations of nuclear widths via an integral relation

Kenneth M. Nollett
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Abstract

I describe the computation of energy widths of nuclear states using an integral over the interaction region of ab initio variational Monte Carlo wave functions, and I present calculated widths for many states. I begin by presenting relations that connect certain short-range integrals to widths. I then present predicted widths for 5 <= A <= 9 nuclei, and I compare them against measured widths. They match the data more closely and with less ambiguity than estimates based on spectroscopic factors. I consider the consequences of my results for identification of observed states in ^8B, ^9He, and ^9Li. I also examine failures of the method and conclude that they generally involve broad states and variational wave functions that are not strongly peaked in the interaction region. After examining bound-state overlap functions computed from a similar integral relation, I conclude that overlap calculations can diagnose cases in which computed widths should not be trusted.

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Kenneth M. Nollett. 2012-05-31. Ab initio calculations of nuclear widths via an integral relation. https://doi.org/10.1103/physrevc.86.044330

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