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Matrix Elements between Nuclear Compound States and Dynamical Enhancement of the Weak Interaction

V. V. Flambaum·O. K. Vorov
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Abstract

A method to calculate the mean squared matrix element of weak interaction between compound states is developed. The result is expressed in terms of matrix elements of the nucleon-nucleon strong and weak interactions times the Fermi distribution functions at finite temperature. Numerical calculations for $^{233}$Th are in excellent agreement with recent measurements of parity nonconservation effects in neutron capture. In fact, our calculations prove that the factor of dynamical enhancement (ratio of compound-nucleus effect to single-particle one) really exceeds 100, thus making it unnesessary to assume a value of the weak constant bigger than standard one ($g\simeq 10^{8} ε\sim 1÷4$).

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V. V. Flambaum, O. K. Vorov. 1997-06-04. Matrix Elements between Nuclear Compound States and Dynamical Enhancement of the Weak Interaction. https://doi.org/10.1103/physrevlett.70.4051

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