R-MATRIX FLOQUET THEORY OF MULTIPHOTON PROCESSES .5. MULTIPHOTON DETACHMENT OF THE NEGATIVE HYDROGEN-ION

Using the recently proposed R-matrix Floquet theory we have performed ab initio calculations for single- and multiphoton detachment of the negative hydrogen ion, H-. Our method is non-perturbative in the field strength and is a multielectron theory allowing for full correlation between the two electrons. We present results depending on frequency up to nonperturbative field intensities for H- in a single-frequency linearly polarized laser. We investigate a wide range of frequencies and intensities from the multiphoton detachment regime to the high-frequency regime. Our results include total detachment rates, shifts of the attachment energy in the field and partial rates into the various excess photon absorption and core excitation partial channels. We compare our results with other theoretical calculations and with experimental results.