The energy distributions for clinically used electron beams from measured and calculated mono energetic depth dose values were calculated. The energy distributions having the minimum difference between the measured and reduced values of depth dose are determined by iterations based on least square method. The nominal energies of 6, 9, 12, 15 MeV clinical electron beams were examined. The Monte Carlo depth dose calculations with determined energy distributions were performed to evaluate those distributions. In a comparison of the calculated and measured depth dose data, the standard errors are estimated within ±3% from surface to R₈₀ depth and within ±4% from the surface to near the range for all electron beams. This can be practically applied to determine the energy distributions for clinically used electron beams.

KeywordsEnergy distribution, Electron beam, Monte Carlo