Disappearance and reappearance of above-threshold-ionization peaks

It is shown that above-threshold ionization peaks disappear when the kinetic energy associated with the nondipole radiation-pressure-induced photoelectron momentum in the laser propagation direction becomes comparable to the photon energy, and how peaks can be made reappear if knowledge of the length and direction of the photoelectron momentum is at hand and an emission-direction-dependent momentum shift is accounted for. The reported findings should be observable with intense mid-infrared laser pulses.