Fig. 2: Schematic diagram of the experimental setup.
From left to right: a beam of negative astatine ions (blue circles) is guided into GANDALPH49,50, where the ion beam is overlapped with a frequency tuneable laser beam (red line) in the interaction region in either co- or counter-propagating geometry. By absorbing a photon (Inset 1), an electron can gain enough energy to be ejected from the ion, thereby creating a neutral atom (green circles, Inset 2). After the interaction region, the charged particles are deflected into an ion detector, while neutralized atoms continue moving straight to the graphene-coated glass plate downstream and create secondary electrons (white circles), which are detected by a channel electron multiplier51.
