Isospin-forbidden electric dipole transition of the 9.64 MeV state of ${}^{12}$C

Y. Suzuki, W. Horiuchi, M. Kimura

The electric dipole transition of the 3${}^{-}$ state at 9.64 MeV of ${}^{12}$C to the 2${}^{+}$ state at 4.44 MeV is speculated to play a key role in the triple-$\alpha$ reaction at high tempera…