Subthreshold resonances in three-particle molecular systems

This paper examines the resonant scattering of a light particle by a pair of identical particles in the Efimov limit. An analytic expression for the resonance widths is derived. The results of calculations are compared with the solution of Faddeev integral equations within a broad range of masses of the light particle. It is shown that the widths of the subthreshold resonances in the scattering amplitude obtained from the integral equations with Yamaguchi potentials are accurately described by the analytic expression, which makes it possible to use this expression in a range of masses inaccessible to numerical calculations. The conclusion is drawn that the lifetime of highly excited negative molecular ions is infinite. Zh. éksp. Teor. Fiz. 115, 1973–1986 (June 1999)