Calculation Of Neutron Energy Deposition In Nanometric Sites

Simulations of charged particle tracks in water vapour were used to build a parametric model enabling the calculation of ionisation distributions in spherical targets, including the influence of straggling and delta rays. The model has been applied to assess neutron energy deposition in nanometric sites in tissue. Emission and slowing down spectra of charged particles from neutron interactions and of photo-induced electrons were combined with the model. All kinds of ionisation events were taken into account, although in such small sites crossers and touchers definitely predominate. The approach has been coupled with macroscopic radiation transport calculations, thus allowing for biophysical modelling of realistic radiobiological situations.