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arXiv · 1103.3622

Chiral two-body currents in nuclei: Gamow-Teller transitions and neutrinoless double-beta decay

J. Menéndez·D. Gazit·A. Schwenk
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Abstract

We show that chiral effective field theory (EFT) two-body currents provide important contributions to the quenching of low-momentum-transfer Gamow-Teller transitions, and use chiral EFT to predict the momentum-transfer dependence that is probed in neutrinoless double-beta decay. We then calculate for the first time the neutrinoless double-beta decay operator based on chiral EFT currents and study the nuclear matrix elements at successive orders. The contributions from chiral two-body currents are significant and should be included in all calculations.

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J. Menéndez, D. Gazit, A. Schwenk. 2011-06-15. Chiral two-body currents in nuclei: Gamow-Teller transitions and neutrinoless double-beta decay. https://doi.org/10.1103/physrevlett.107.062501

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