Chiral effective field theory calculations of weak transitions in light nuclei

Abstract

Quantum Monte Carlo calculations of electroweak transitions are performed for $A\ensuremath{\le}10$ nuclei based upon two- and three-nucleon chiral interactions and the associated one- and two-body axial currents. Except for $\ensuremath{\beta}$ decay of ${}^{8}$He, ${}^{8}$Li, and ${}^{8}$B, two-body currents contribute less than 3%. The exceptional nuclei exhibit matrix elements suppressed in impulse approximation based on the leading order (GT) transition operator. For a given interaction, the two-body transition densities exhibit a universal behavior at short distance for all systems under study.