Radiobiology of alpha particles. II. Dosimetry of low-energy alpha particles using parallel-plate ionization chambers and a surface barrier detector.
Three small parallel-plate ionization chambers were developed for measuring dose rates, of primarily low-energy alpha particles in the energy range 0.4-3.5 MeV, at a defined cell-Mylar interface. Spectral energy distributions of these alpha particles were also measured at the same position using a specially designed small-area silicon surface barrier detector. Dose rates were derived from the spectral distributions and compared with those derived from the ionization chambers. Different alpha-particle energies were obtained using a 144-MBq 238Pu collimated source and a variety of Mylar moderator foils of different thicknesses. These measurements, extended to mean alpha-particle energies as low as 0.4 MeV, will enable us to correlate radiobiological data with effects of alpha particles terminating in different regions of cell nuclei.
Eisen
Y
Y
Dose Assessment Section, Los Alamos National Laboratory, New Mexico 87545.
Harvey
W F
WF
Raju
M R
MR
D000512:Alpha Particles; D011829:Radiation Dosage