Inactivation of Dry T-1 Bacteriophage by Helium Ions, Carbon Ions, and Oxygen Ions: Comparison of Effect for Tracks of Various Ion Density

Abstract

Dry preparations of T-l bacteriophage were irradiated with helium ions and with stripped carbon and oxygen ions, extending previous studies of effect of linear energy transfer (LET) to values unattainable with a-particles. Over a wide range in LET the effect on phage survival is a function only of the radiation dose, but for heavy ions the efficiency does decrease. A minimum requirement of either one or two ions in a track interval only a few angstrom units long is indicated for inactivation of plaque survival. The indication is against a higher minimum number of ions required. On interpretation in terms of target area, correction for [delta] -rays brings the phage target within morphological bounds.