Study of the photodetachment ofC−andF−by many-body perturbation theory

Abstract

Photodetachment cross sections of ${\mathrm{C}}^{\ensuremath{-}}$ and ${\mathrm{F}}^{\ensuremath{-}}$ are calculated by means of the many-body perturbation theory with multiple basis sets. The ${V}^{N\ensuremath{-}1}$ basis set is defined to include the intrachannel interaction. The ${V}^{N\ensuremath{-}2}$ basis set is introduced to describe the correlation in the Hartree-Fock ground states of negative ions. The lowest-order cross sections agree very well with experiment. The first-order corrections are calculated in the case of ${\mathrm{F}}^{\ensuremath{-}}$, and a large cancellation is found between the initial-state correlation and the final-state interchannel interactions. The importance of the use of the energy relations in the lower-order calculations is pointed out.