The Monte Carlo code, BEAMnrc, is used to model components of the therapy head of a medical linac, and the transportation process is simulated for photons produced by 6MV electron beam bombarding a tungsten target in the therapy head. The particle phase space information is obtained on a therapy plane with a 100cm source to surface distance and a 10cm 10cm opening field size. Results of energy fluence distributions, energy spectra, mean energy distributions and angular distributions of particles are pr...
