The quenching of the axial-vector coupling constant $g_A$ in ${\hat{I}}^2$-decay: joint effects from chiral two-body currents and many-body correlations

Bin-Lei Wang, Wan-Li Lv, Li-Gang Cao +4

In nuclear ${\hat{I}}^2$-decay calculations, the axial-vector coupling constant $g_A\approx 1.27$ usually needs to be quenched phenomenologically by a factor $q\approx$ 0.75 to reproduce…