ABOVE-THRESHOLD IONIZATION SPECTRUM OF HYDROGEN USING B-SPLINE FUNCTIONS

We present a method for the accurate calculation of above-threshold io nization (ATI) spectra of single active electron systems. The techniqu e involves the expansion of the radial wavefunction onto a set of B-sp line functions. Results of ATI in hydrogen are presented and particula r features of the spectra are discussed. A detailed study of the sensi tivity of the results to the critical parameters is given to emphasize the importance of the necessity of a high degree of convergence in su ch calculations. Finally, we discuss and quantitatively justify the us e of L(2) methods in investigations of ATI.