Thindown in radiobiology: V-79 Chinese hamster cells

Calculations based on the track theory of biological cells agree with measured inactivation cross sections for V-79 Chinese hamster cells bombarded with very heavy ions in the track width regime where thindown, a reduction in cross section with an increase in the LET of the bombarding particles, is displayed. The calculation uses cellular radiosensitivity parameters evaluated earlier from the data of survival curves and a new numerical calculation of the radial distribution of dose from δ-rays. These results represent a significant improvement over an earlier calculation of the same endpoint, where a formulation of the radial dose distribution which neglected the angular distribution of ejected δ rays was used