Corresponding aspects of strong-field multiquantum processes and ion-atom collisions

An approximate correspondence between collisional processes and the interaction of atoms with intense short pulses of radiation yields simple relations connecting the parameters governing these two classes of phenomena. This correspondence can be visualized by the consideration of suitable constructed trajectories representing the radiative (multiphoton) and collisional interactions. Comparisons of spectral data in the extreme ultraviolet region for Ne, Ar, Kr, and Xe produced by collisional excitation and subpicosecond ultraviolet laser irradiation indicate approximate conformance with the expectations stemming from this analysis. These results suggest that, for ultraviolet radiation, this approach may be useful in understanding the gross features of the strong-field multiquantum interaction over the range of intensity spanning from ~10¹⁶ W/cm² to ~10²¹ W/cm ²