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Exact evaluation of the nuclear form factor for new kinds of majoron emission in neutrinoless double beta decay

C. Barbero·J. M. Cline·F. Krmpotic·D. Tadic
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Abstract

We have developed a formalism, based on the Fourier-Bessel expansion, that facilitates the evaluation of matrix elements involving nucleon recoil operators, such as appear in serveral exotic forms of neutrinoless double beta decay ($ββ_{0ν}$). The method is illustrated by applying it to the ``charged'' majoron model, which is one of the few that can hope to produce an observable effect. From our numerical computations within the QRPA performed for $^{76}Ge$, $^{82}Se$, $^{100} Mo$, $^{128}Te$ and $^{150}Nd$ nuclei, we test the validity of approximations made in earlier work to simplify the new matrix elements, showing that they are accurate to within 15%. Our new method is also suitable for computing other previously unevaluated $ββ_{0ν}$ nuclear matrix elements.

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C. Barbero, J. M. Cline, F. Krmpotic, D. Tadic. 1996-09-24. Exact evaluation of the nuclear form factor for new kinds of majoron emission in neutrinoless double beta decay. https://doi.org/10.1016/s0370-2693(96)01587-0

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