Vv. Flambaum et Ok. Vorov, MATRIX-ELEMENTS BETWEEN NUCLEAR-COMPOUND STATES AND DYNAMICAL ENHANCEMENT OF THE WEAK INTERACTION, Physical review letters, 70(26), 1993, pp. 4051-4055
A method to calculate the mean squared matrix element of the weak inte
raction between compound states is developed. The result is expressed
in terms of matrix elements of the nucleon-nucleon strong and weak int
eractions times the Fermi distribution functions at finite temperature
. Numerical calculations for Th-233 are in excellent agreement with re
cent measurements of parity nonconservation effects in neutron capture
. In fact, our calculations prove that the factor of dynamical enhance
ment (ratio of compound-nucleus effect to single-particle one) really
exceeds 100, thus making it unnecessary to assume a value of the weak
constant bigger than standard one (g congruent-to 10(8) epsilon is sim
ilar to 1-4).