Fig. 4From: PENELOPE/PRIMO-calculated photon and electron spectra from clinical acceleratorsPhoton spectra for 6 and 10 MV beams, derived from the PSF for a 10 cm × 10 cm field, for a central circular area of 2 cm diameter and a square of 2 cm side using bin widths of 50 keV, and for a square of 10 cm side using bin widths of 1, 50 and 250 keV. All the spectra are normalized to their respective integral. Note the energy logarithmic scale for better visualizationBack to article page