The effects of the microscopical theory of the Coriolis forces on nuclear beta-decay155Eu →155Gd

Abstract

The wave functions yielded by the microscopical non-adiabatic treatment of the Coriolis interaction proposed in Dubna by Pyatov, Chernej and Baznat have been used in order to calculate the beta decay observables of some allowed transitions of the 155Eu nucleus. The Coriolis interaction effects are important especially for the absolute ft values (an important improvement is obtained) and for the fl-y circular polarization correlation.

About the correction matrix element effects on the first-forbidden beta decays of the155Eu nucleus

“…[1]. From Table 1 we notice that besides the matrix elements which usually are the only ones considered in the old formalism for the first-forbidden transitions, namely:…”

“…[1], according to the (10) and (11) formulas. However the expression of the formula (12) is modified because we have to do with transitions between pure states in contrast with the calculations of the previous paper.…”

“…For the superfluid corrections, R, of the (ft)R values, we used the same superfluid parameters as in Ref. [1].…”

“…A satisfactory agreement between theory and experiment has been found for the absoluteft values. By satisfactory agreement we mean the following conditions: 1< (fct)exp ~,r, (fj)~--<~ tu (1) where by (fc t)R we denoted the calculated fc t value corrected with the superfluid correction factor, R.…”

“…In a previous paper [1] the calculation of the observables for the allowed beta decays a55Eu~SSGd has been carried out. The final states of these transitions are positive parity levels and their eigenvalues are obtained theoretically by solving the Schr6dinger equation with a Coriolis forces term included in the corresponding nuclear Hamiltonian [2][3][4].…”