Figure 9.

The effect of modelled crystal geometry on the calculated DWD (MGy) values has been illustrated for four crystal shapes, each with a total volume of 10⁶ µm³. Dose isosurfaces are contoured at 0.001 MGy (light blue), 20 MGy (dark blue) and 30 MGy (red), using R (www.r-project.org). In (a) and (b), two irregular polyhedron‐shaped crystals were generated using the open‐source three‐dimensional graphics software called Blender. In (c) and (d) the “Type cuboid” and “Type spherical” input file parameters to RADDOSE‐3D have been used to model the crystal as a 100 µm × 100 µm × 100 µm cuboid, and a 124.2 µm diameter sphere, respectively. In all simulations, a Gaussian beam (12.4 keV, 1e11 ph/s) was modelled with FWHM of 20 µm × 20 µm, in order to obtain the infamous “fried egg” effect.