Investigation of fragment doses produced by heavy ions in tissue-like material.

In this paper, the distribution of fragments produced by 55 MeV/n 4°Ar¹7⁺ ions in tissue-equivalent material is reported as a function angles relative to the incident particle direction. The relative fragment doses at different angles and the total dose due to the primary beam have been estimated. The results show that the fragments produced by primary beam were concentrated at very small angles, so the fraction of particle fluence diverging from the primary beam was very small. Even though the diverging fluence is a small fraction of the total, it should still be taken into account because biological systems are very sensitive to low doses of heavy ion irradiation.