Multiphoton detachment of an electron fromH−

The generalized multiphoton detachment cross sections for n=1–7 photons are evaluated for ${\mathrm{H}}^{\mathrm{-}}$ in a zero-range plane-wave approximation. Results are compared with the recent experiments of Tang et al. [Phys. Rev. A 39, 6068 (1989)] and Smith et al. [J. Opt. Soc. Am. (to be published)] on these processes using relativistic ${\mathrm{H}}^{\mathrm{-}}$ beams interacting with Doppler-shifted ${\mathrm{CO}}_2$ laser pulses. Many features of the data are qualitatively consistent with the present calculation, but significant differences in shape and magnitude still remain.