2014/03/31 by J. Engel, Engel, J., F. Šimkovic +4
Physics and Astronomy · #Atomic and Subatomic Physics Research #FOS: Physical sciences #Neutrino Physics Research #Nuclear Theory (nucl-th) #Quantum, superfluid, helium dynamics #nucl-th
paper · pdf · doi:10.48550/arxiv.1403.7860
6 pages, 2 figures
arxiv created 2014/03/31 · openalex publication_date 2014/03/31 · arxiv updated 2014/04/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We test the effects of an approximate treatment of two-body contributions to the axial-vector current on the QRPA matrix elements for neutrinoless double-beta decay in a range of isotopes. The form and strength of the two-body terms come from chiral effective-field theory. The two-body currents typically reduce the matrix elements by about 20%, not as much as in shell-model calculations. One reason for the difference is that standard practice in the QRPA is to adjust the strength of the isoscalar pairing interaction to reproduce two-neutrino double-beta decay lifetimes. Another may be the larger QRPA single-particle space. Whatever the reasons, the effects on neutrinoless decay are significantly less than those on two-neutrino decay, both in the shell model and the QRPA.