When this article was originally published in High Power Laser Science and Engineering it contained an incorrect version of Figure 6. The correct version of Figure 6 can be found below:
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Figure 6 (a) Proton beam profile used for Geant4 simulations. (b) Sinograms generated from selected layers of the SciFi stack. (c) MLEM reconstructions of the energy deposited in the selected SciFi stack layers. Regions of interest with a radius of
$2{\sigma}_{\mathrm{beam}}$
are used for evaluating the reconstructed energy deposited by each beamlet, and are shown with white dashed lines.
The publisher apologises for this error.