A complex resonance-scattering theory is developed to obtain partial widths and branching ratios for full scattering experiments. A new formula for the partial widths which is useful in atomic, molecular, nuclear, and particle physics is obtained. The formalism provides a simple relationship among the previously proposed different methods for calculating partial widths. Illustrative numerical examples are given, showing the stability (lack of oscillations) of the partial widths obtained by this formula.

• Received 20 February 1990

DOI:https://doi.org/10.1103/PhysRevA.42.255