Spin propensity rules for three-body recombination of ultracold alkali-metal atoms*

We present a theoretical study on the spin-propensity rule for the final state distribution of three-body recombination for all commonly used alkali-metal atoms. Three-body recombination is a chemical reaction in which three atoms collide to produce a diatomic molecule which can further detected in molecular ionization experiments. Our previous studies with Rubidium atoms have shown that most of the molecular states formed in recombination have the same hyperfine spins as those of the colliding atoms. Our current study, however, shows that the conservation of the hyperfine spins is dependent on the strength of the electronic spin-exchange. We find that various atomic species violate such conservation rule, while still displaying propensity rules related to the binding energy of the molecular products.