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Two neutrino double beta decay within the $ξ$-approximation

C. Barbero·F. Krmpotić·A. Mariano
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Abstract

We examine the contributions of odd-parity nuclear operators to the two-neutrino double beta decay $0^+\rightarrow 0^+$ amplitude, which come from the $P$-wave Coulomb corrections to the electron wave functions and the recoil corrections to the nuclear currents. Although they are formally of higher order in $αZ/2$ or $v/c$ of the nucleon than the usual Fermi and Gamow-Teller matrix elements, explicit calculations performed within the QRPA show that they are significant when confronted with the experimental data.

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C. Barbero, F. Krmpotić, A. Mariano. 1994-12-09. Two neutrino double beta decay within the $ξ$-approximation. https://doi.org/10.1016/0370-2693(94)01592-z

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