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arXiv · 1906.04143

Bayesian analysis of capture reactions $^3\mathrm{He}(\alpha,\gamma)^7\mathrm{Be}$ and $^3\mathrm{H}(\alpha,\gamma)^7\mathrm{Li}$

Pradeepa Premarathna·Gautam Rupak
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Abstract

Bayesian analysis of the radiative capture reactions $^3\mathrm{He}(\alpha,\gamma)^7\mathrm{Be}$ and $^3\mathrm{H}(\alpha,\gamma)^7\mathrm{Li}$ are performed to draw inferences about the cross sections at threshold. We do a model comparison of two competing effective field theory power countings for the capture reactions. The two power countings differ in the contribution of two-body electromagnetic currents. In one power counting, two-body currents contribute at leading order, and in the other they contribute at higher orders. The former is favored for $^3\mathrm{He}(\alpha,\gamma)^7\mathrm{Be}$ if elastic scattering data in the incoming channel is considered in the analysis. Without constraints from elastic scattering data, both the power countings are equally favored. For $^3\mathrm{H}(\alpha,\gamma)^7\mathrm{Li}$, the first power counting with two-body current contributions at leading order is favored with or without constraints from elastic scattering data.

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Pradeepa Premarathna, Gautam Rupak. 2019-06-10. Bayesian analysis of capture reactions $^3\mathrm{He}(\alpha,\gamma)^7\mathrm{Be}$ and $^3\mathrm{H}(\alpha,\gamma)^7\mathrm{Li}$. https://doi.org/10.1140/epja/s10050-020-00113-z

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