267 nm. Laser polarization is vertical.
Sept 2001

At 267 nm the situation is dramatically different from 400nm. First, both spin-orbit states of the I atom are produced, resulting in a bi-modal structure of the photoelectron image. The photoelectrons are recoiling much faster now. Note that the scaling of the 400 and 267 nm images is not the same. In the former case, the photoelectron cloud was allowed to expand 2.7 times longer than in the latter.
Second, so far from the detachment threshold, the d partial wave has a significant amplitude, which enables it to compete with the isotropic s wave. As a result, the photoelectron image exhibits substantial angular anisotropy, polarized perpendicular to the laser polarization.

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The figure below shows the 400 and 267 nm images with proper relative scaling.