An optimized C6D6 detector for studies of resonance-dominated (n,γ) cross-sections

Hydrogen-free scintillators are indispensable for determining the small, resonance-dominated neutron capture cross-sections of light and neutron magic nuclei, data which are needed for advanced reactor concepts, for transmutation of radioactive wastes as well as for astrophysical scenarios of neutron capture nucleosynthesis. A critical comparison of the existing detector concepts by means of detailed GEANT simulations revealed large differences in neutron sensitivity. Based on these simulations, an optimized detector was developed and successfully tested. Compared to a commercial detector, the neutron sensitivity of this solution is more than an order of magnitude lower, thus allowing even extremely small capture/scattering ratios to be measured reliably.