Dynamics of strong-field above-threshold ionization of argon: Comparison between experiment and theory

We record angle-resolved electron-momentum distributions from 800-nm short-pulse laser ionization of argon and compare our data with numerical solutions of the time-dependent Schrödinger equation. A model potential of argon and the single active electron approximation are used. The calculation shows quantitative agreement in all dominant features of the experimental results. The energy and angular distributions of the photoelectrons, together with numerical simulations, allow us to identify the multiple processes involved during the interaction, such as channel switching, multiphoton resonant and nonresonant ionization, and ac Stark splitting.