Microdosimetry of range-modulated beams of heavy ions. I. Determination of the yield of projectile fragments from microdosimetric spectra for neon-10 beams

A method for the calculation of projectile fragmentation spectra from microdosimetric distributions for heavy ions is proposed. The fundamental quantity determined in microdosimetric measurements is the distribution of energy deposited in a specified volume. It is known that, for high-energy heavy-ion beams, the nuclear interactions are dominated by projectile fragmentation in which the secondary particles are emitted with a velocity nearly equal to that of the primary particle. Therefore, it is possible to calculate the distribution of energy deposited for each particle type; the microdosimetric spectra can then be used to determine the relative contributions from each type of particle. Experimental microdosimetric data obtained for a range-modulated beam of 557 MeV/amu neon ions are presented and the data in the plateau are analyzed as an example of this technique.