Abstract
A comparison is made of the ratios of the squares of the Gamow-Teller and Fermi coupling constants, , calculated from the latest experimental values and the theoretical matrix elements for the "doubly closed shell±one nucleon" mirror transitions and the - transitions. The value of the neutron derived from the recent half-life measurement of 11.7±0.3 minutes leads to a value for of 1.42±0.06, which is in agreement with the ratio obtained from the correlation coefficient for the betaparticle momentum and the spin direction of the decaying neutron. The value for the decay of is also in good agreement with this ratio if the Gamow-Teller matrix element for this transition does not differ appreciably from that predicted by the individual particle model. The value of the heavier mirror nuclei, , and , are consistent with a considerably lower ratio. In particular, and , for which the Gamow-Teller matrix elements are considered the most reliable because the magnetic moments of the daughter nuclei are especially close to the Schmidt limits, lead to a value for of 1.16±0.05. These results are consistent with recent theoretical considerations which suggest that meson exchange effects may give rise to appreciable corrections in the calculation of the matrix elements.
- Received 9 January 1959
DOI:https://doi.org/10.1103/PhysRev.114.1329
©1959 American Physical Society