Knowledge of the x-ray spectra enables system designers to predict patient dose accurately and develop better methods to reduce patient dose. Consequently, it is important to correctly implement these cross sections within Monte Carlo (MC) codes, such as EGSnrc.
X-ray spectra of low energy electron impacting on tungsten, molybdenum, and titanium are calculated using the EGSnrc BEAMnrc code with two Electron Impact Ionization (EII) cross-sections, one implemented by Kawrakow and another by Salvat (Penelope cross-sections).
The spectra calculated with the two cross sections are compared to
experimental ones obtained by Tian et .al ant PTB. It is found that agreement is less than satisfactory when using the Penlope data, while the Kawrakow cross sections underestimate the values for the characteristic x-ray peaks. Further these differences are analyzed through air kerma calculations. Overall, the results indicate that further investigation into the theoretical aspects of EII is required.