On the probability of artificial nuclear transformations and its connection with the vector model of the nucleus

The theorem of quantum mechanics that “the spin part of the angular momentum is approximately a constant of motion provided that the forces depending on the direction of the spins are small compared with the total interaction forces” is introduced into the discussion of artificial nuclear transformations. A definition is given for the terms “probable” and “not probable” nuclear reaction. 2. Attention is drawn to the experimental result that the reaction Li 6 + H 1 → He 4 + He 3 is more probable than the reaction Li 7 + H 1 → 2He 4 , and an explanation is suggested. 3. The nuclear spin of Lie is derived from nuclear transformations and found to be 1. 4. Similar derivations for the spins of H 3 , He 3 and B 11 are summarised in a table.