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arXiv · 1411.4829

The chiral long-range two-pion exchange electromagnetic currents in radiative nucleon-deuteron capture

R. Skibinski·J. Golak·D. Rozpedzik·K. Topolnicki·H. Witala
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Abstract

The nucleon-deuteron radiative capture process is investigated using the chiral nuclear potentials and the electromagnetic currents developed by the Bochum-Bonn group. While the strong interaction is taken up to the next-to-next-to-leading order, the electromagnetic current consists of a single nucleon current, the leading one-pion exchange one and is supplemented by contributions from the long-range two-pion exchange current at next-to-leading-order. The theoretical predictions for the cross sections as well as analyzing powers show strong dependence on the values of regularization parameters. Only small effects of the three-nucleon force and the long-range two-pion exchange current are observed. The dependence on the choice of regularization parameters results in a big theoretical uncertainty and clearly points to the necessity to include corrections from higher orders of the chiral expansion both for the nuclear forces and currents.

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R. Skibinski, J. Golak, D. Rozpedzik, K. Topolnicki, H. Witala. 2014-11-18. The chiral long-range two-pion exchange electromagnetic currents in radiative nucleon-deuteron capture. https://doi.org/10.5506/aphyspolb.46.159

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