Abstract： We theoretically study the pulse-width dependence of the photoelectron angular distribution (PAD) from the resonance-enhanced two-photon single ionization of He by femtosecond (& 20 fs) extreme- ultraviolet pulses, based on the time-dependent perturbation theory and simulations with the full time- dependent Schro ̈dinger equation. In particular, we focus on the competition between resonant and nonresonant ionization pat...