Standard closed-orbit theory is applied to derive the photodetachment cross section of ${\mathrm{H}}^{-}$ in the presence of a static electric field. The result agrees with the one derived earlier using a quantum approach involving a momentum-space wave function and stationary-phase approximation. The advantage of the present derivation is the ability to separate the oscillation term and the smooth background term in the photodetachment cross section and to identify the two terms with different physical origins.

• Received 17 August 2004

DOI:https://doi.org/10.1103/PhysRevA.70.055402