MULTIPHOTON RESPONSE OF HE TO SHORT LASER-PULSES OF WAVELENGTH 248 NMAND INTENSITIES IN THE RANGE 10(14)-10(16) W CM(-2)

The state-specific expansion approach to the solution of the time-depe ndent Schrodinger equation was applied to the calculation of aspects o f the multiphoton response of He to short laser pulses of lambda = 248 nm and I = 10(14)-10(16) W cm(-2). Ionization rates and probabilities , saturation intensity and generalized cross sections are compared wit h recent experimental findings by Charalambidis et al. Above-threshold ionization spectra and the corresponding photoelectron angular distri butions show a minor dependence on the temporal shape of the pulse.