Stopping Powers for Electrons and Positrons-2464713B

ICRU Report No. 37 represents the first result of a series of Commission efforts concerned with stopping power. Subsequent efforts will treat particles and ions heavier than electrons. Being the first of the series, Report 37 reviews topics which are pertinent to the evaluation of stopping powers for any charged particle, such as shell corrections and the determination of mean excitation energies. In treating electrons, the report focuses on topics which are pertinent, mainly or entirely, to electrons, including radiative stopping power due to the emission of bremsstrahlung, refined estimates of the density effect and the information on electron collision stopping power at energies below 10 keV. Stopping power tables are presented for a large number of elements and compounds covering the energy range from 10 keV to 1000 keV. The tables also include the range and radiation yield. Throughout the report, the requirements for up-to-date stopping power information in biomedical dosimetry are emphasized. Major sections of the report treat formulae for collision stopping power, methods for estimating mean excitation energies, selection of mean excitation energies for elements and compounds, density effect, restricted collision stopping power, electron collision stopping powers at low energies, radiative stopping power, ranges and radiation yields.