Theoretical and Experimental Radiation Effectiveness of the Free Radical Dosimeter Alanine to Irradiation with Heavy Charged Particles

Abstract

Dose-response characteristics have been measured for the crystalline amino acid L-α-alanine irradiated with ion beams of 6 and 16 MeV protons, 20 MeV α particles, 21 MeV ${}^{7}{\rm Li}$ ions, 64 MeV16 O ions, and 80 MeV ${}^{32}{\rm S}$ ions. The experimental radiation effectiveness (RE) with reference to low-LET radiations of60 Co γ rays, 4 and 16 MV X rays, and 6, 10, and 20 MeV electrons was compared with theoretical RE values derived from a model based on track structure theory of heavy charged particles. The ion beams covered a range in initial LET of $27-20,200 {\rm MeVcm}^{2}/{\rm g}$ , and the experimental RE decreased with increasing LET being 1.00 for 16 MeV protons and 0.25 for the 80 MeV ${}^{32}{\rm S}$ ions. The calculated Re values were in acceptable agreement with the experimental results having a maximum deviation of 8% for the ${}^{7}{\rm Li}$ and ${}^{32}{\rm S}$</tex-math...