Gamow–Teller transition

A Fermi transition or a Gamow–Teller transition are types of nuclear beta decay determined by changes in angular momentum or spin. In the Fermi transition, the spins of the emitted particles are antiparallel, coupling to ${\displaystyle S=0}$, so the angular momentum of the initial and final angular momentum states of the nucleus are unchanged (${\displaystyle \Delta J=0}$). This is in contrast to a Gamow-Teller transition, where the spins of the emitted electron (positron) and antineutrino (neutrino) couple to total spin ${\displaystyle S=1}$, leading to an angular momentum change ${\displaystyle \Delta J=0,\pm 1}$ between the initial and final angular momentum states of the nucleus.

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