Production of Energetic Electrons in the Process of Photodetachment of ${\mathrm{F}}^{-}$

An imaging technique is used to record an energy and angle resolved spectrum of electrons produced by photodetachment of ${\mathrm{F}}^{-}$ in a strong infrared laser pulse. The spectrum involves contributions from more than 23 excess photon detachment channels. Its higher energy part extends beyond the classical cutoff value, and it appears as a pronounced plateau localized within a small angle along the laser polarization axis. A Keldysh-like theory is able to qualitatively reproduce the spectrum without taking into account the rescattering mechanism. The role of the parity of the initial bound state is discussed.

Figure 1

Angle resolved photoelectron spectrum. The upper part shows the experimental result; the lower part is a simulation using the Keldysh-like theory [11] and explicitly accounting for our experimental parameters.

Figure 2

Energy distribution of photoelectrons emitted along the laser polarization axis. Dots, experimental data; solid line, calculations for $\ell =1$ [11]; dashed and dotted lines, calculations for $\ell =0$ with [13] and without [11] the rescattering effect taken into account, respectively. The arrow indicates the classical cutoff energy.