Radiological physics

Methods used for the dosimetry of monoenergetic neutrons in rats yielded information on the γ dose and dose received from scattered radiation during neutron beam exposure. Results are reported from studies on the effects of neutron irradiation on the induction of somatic mutations in Tradescantia and the induction of chromosome aberrations in root tip cells of Vicia faba and Allium cepa. The neutron and photon (x and γ) tissue kermas in free air and absorbed dose in a tissue-equivalent phantom were measured for four energies of monoenergetic neutrons (15.1, 5.5, 2.1, and 0.67 MeV) and a 252Cf source of fission neutrons. Callibrations were made using a 137Cs γ source. The accuracy of the various dosemeters used is discussed. An apparatus is described that was constructed for irradiating mammalian cells with beams of charged particles. Methods for the microdosimetry of charged particles and monoenergetic photons (x and γ) are discussed in detail. (U.S.)