Radiation spectra for Auger-electron emitting radionuclides: report No. 2 of AAPM Nuclear Medicine Task Group No. 6

Abstract

Radiation spectra for radionuclides currently provided by the MIRD Committee and ICRP do not include the very low-energy N- and O-shell Auger electrons. These electrons, emitted in large numbers by radionuclides decaying by electron capture and/or internal conversion, are important for determining the absorbed dose in microscopic volumes. Accordingly, the present AAPM Report employs Monte Carlo computational methods to obtain a self-consistent set of complete radiation spectra for a variety of radionuclides including 55Fe, 67Ga, 99mTc, 111In, 113mIn, 115mIn, 123I, 125I, 193mPt, 195mPt, 201Tl, and 203Pb. Although the conventional spectra provided by MIRD and ICRP are adequate for most dosimetry calculations, the Auger electron spectra provided in this report are recommended for calculating the dose to target volumes < 1 microns in diameter.