First \textit{ab initio} calculations of first-forbidden ${\hat{I}}^2$ transitions in the reactor antineutrino anomaly

X. Y. Xu, Z. Y. Meng, Z. C. Xu +1

Forbidden ${\hat{I}}^2$ transitions are important for understanding the reactor antineutrino anomaly. Starting from chiral two- plus three-nucleon forces, we have derived the valence-space…