Figure 7
Calculated small beam enhancement, defined as the ratio of the total energy deposited in the crystal relative to that actually deposited in the beam volume, as a function of the beam diameter for incident X-ray energies of 8.1 keV (dashed line), 12.7 keV (unbroken line) and 15 keV (dotted line). The inset shows the calculated deposited energy density per generated 12.7 keV photoelectron as a function of radius for a 20 µm thick sample illuminated by a 1 µm diameter beam. On average, 12.1 keV is deposited in the whole crystal but only 1.4 keV of this is contained within the illuminated volume (indicated by the shading). |