Impact of atomic Rydberg state excitation on the radiation spectrum generated in short intense laser pulses*

The impact of highly excited (Rydberg) states on strong-field induced high harmonic generation and ionization has been of recent interest. Utilizing {\it ab initio} simulations of the Time Dependent Schr\"{o}dinger Equation and systematically selecting laser intensities and frequencies, the distribution across the angular momentum states is analyzed for resonant absorption of odd and even number of photons. Furthermore, signatures of the population in the excited states in the radiation spectrum generated during the pulse and after the pulse are identified.