Three-body recombination in cold helium–helium–alkali-metal-atom collisions

Abstract

Three-body recombination in helium-helium--alkali-metal collisions at cold temperatures is studied using the adiabatic hyperspherical representation. The rates for the three-body recombination processes $^{4}\text{H}\text{e}+^{4}\text{H}\text{e}+X\ensuremath{\rightarrow}^{4}\text{H}\text{e}+^{4}\text{H}\text{e}X$ and $^{4}\text{H}\text{e}+^{4}\text{H}\text{e}+X\ensuremath{\rightarrow}{^{4}\text{H}\text{e}}_{2}+X$, with $X=^{7}\text{L}\text{i}$, $^{23}\text{N}\text{a}$, $^{39}\text{K}$, $^{85}\text{R}\text{b}$, and $^{133}\text{C}\text{s}$, are calculated at nonzero collision energies by including not only zero total angular momentum, $J=0$, states but also $J>0$ states. The three-body recombination rates show a relatively weak dependence on the alkali-metal species, differing from each other only by about one order of magnitude, except for the $^{4}\text{H}\text{e-}^{4}\text{H}\text{e-}^{23}\text{N}\text{a}$ system.