LAUSR

Abstract: It is recognized today that the observable radiobiological effects of ionizing radiations are strongly correlated to the local density of lesions produced in micrometer- and nanometer-sized subcellular structures, and thus to the track structure properties of interacting particles. In view of the emerging interest of carbon ions in radiotherapy, an experimental study was done for characterizing the track structure of carbon ions at different energies close to the Bragg peak. Ionization cluster size distributions for nanometer-sized target volumes were measured with the Startrack-Counter installed at the TANDEM-ALPI accelerator complex at LNL, and calculated by means of a dedicated Monte Carlo code. Measurements and simulations were performed for particle tracks crossing directly the target volume or passing nearby at specified impact parameters. Results will be presented and discussed for 12C-ions at 6, 8, 12.5 and 20 MeV per nucleon.