English

Gamow-Teller and double-beta decays of heavy nuclei within an effective theory

Nuclear Theory 2018-10-05 v2

Abstract

We study β\beta decays within an effective theory that treats nuclei as a spherical collective core with an even number of neutrons and protons that can couple to an additional neutron and/or proton. First we explore Gamow-Teller β\beta decays of parent odd-odd nuclei into low-lying ground-, one-, and two-phonon states of the daughter even-even system. The low-energy constants of the effective theory are adjusted to data on β\beta decays to ground states or Gamow-Teller strengths. The corresponding theoretical uncertainty is estimated based on the power counting of the effective theory. For a variety of medium-mass and heavy isotopes the theoretical matrix elements are in good agreement with experiment within the theoretical uncertainties. We then study the two-neutrino double-β\beta decay into ground and excited states. The results are remarkably consistent with experiment within theoretical uncertainties, without the necessity to adjust any low-energy constants.

Keywords

Cite

@article{arxiv.1708.06140,
  title  = {Gamow-Teller and double-beta decays of heavy nuclei within an effective theory},
  author = {Eduardo Antonio Coello Pérez and Javier Menéndez and Achim Schwenk},
  journal= {arXiv preprint arXiv:1708.06140},
  year   = {2018}
}

Comments

17 pages, 5 figures, results extended to two-neutrino double beta-minus decays and two-neutrino double electron-capture decays to excited 2+ states, matches published version