On the use of additivity rules to estimate electron production cross sections in proton-biomolecule collisions

Additivity rules are employed to estimate electron production cross sections for proton collisions with nucleobases and amino acids, using as input experimental data for proton collisions with atoms and small molecules. Cross sections (total and single differential, in electron energy) are calculated for collision energies 10 keV <= E <= 2 MeV. The results show that this simple procedure yields cross sections in good agreement with the available experimental and theoretical cross sections at high collision energies and it is able to reproduce the energy dependence of the total cross sections, including the presence of maxima at intermediate energies.