Nuclear structure calculation of β + β +, β +/EC and EC/EC decay matrix elements
Abstract
Nuclear matrix elements for double positron emisson ( β + β +), positron emission/electron capture ( β +/ EC) and double electron capture (EC/EC) in the 2 νββ decay mode and for β + β + and β +/EC decay in the 0 νββ mode are calculated for the experimentally most promising isotopes58Ni,78Kr,96Ru,106Cd,124Xe,130Ba and136Ce within pn-QRPA. We point out that the matrix element for the 2 νβ +/EC decay differs from the 2 νβ + β + matrix element, an effect not considered previously. For the neutrino accompanied decays our calculation predicts for the β +/EC and the EC/EC mode half lives which are shorter typically by 4 7 orders of magnitude than those for the double positron emission. However, even for the best candidates typical values for 2 νβ +/EC (2 ν EC/EC) are still in the range of ∼1022 (( some) 1021) years. For 0 νββ decay we have calculated all matrix elements relevant for both, the mass mechanism and the right-handed currents for the first time complete. A detailed discussion of the differences between the 0 νβ +β+, the 0 νβ +/EC and 0 νβ - β - decay is given.
- Publication:
-
Zeitschrift fur Physik A Hadrons and Nuclei
- Pub Date:
- September 1994
- DOI:
- 10.1007/BF01292371
- Bibcode:
- 1994ZPhyA.347..151H
- Keywords:
-
- 21.60;
- 23.40