Simulation of heavy-ion slowing-down tracks with the SCENA code

In the frame of dependable neutron flux instrumentation development for Generation IV reactors, the French Atomic and Alternative Energies Commission (CEA) investigates an innovative technology based on optical signal produced within a fission chamber. In such gaseous detectors, neutrons interact with fissile material, releasing heavy ions in the MeV range, eventually leading to spontaneous photons emission in the ultraviolet to infrared range. We hereby present the space–time evolution of heavy-ion slowing-down tracks parameters in noble gases, as computed with the SCENA radiation-induced cold-plasma simulation tool. Preliminary results on excited-states noble-gas population dynamic are reported. Population of upper-lying gas levels is completed within picoseconds, only micrometres behind the projectile ionization trail.