Activation of 197Au and 209Bi in a fast spectrum sub-critical assembly composed of 500Â kg natural uranium irradiated with 1 and 4Â GeV deuterons

The Quinta assembly of the Joint Institute for Nuclear Research (JINR), Dubna, Russia consists of 512 kg of natural uranium rods arranged hexagonally and surrounded by a lead reflector. The setup was irradiated with 1 and 4 GeV deuterons and the (n,γ) and (n,xn) reaction rates of gold and bismuth samples located inside the assembly were determined through gamma spectrometry. The experimental reaction rates were compared to those calculated via the MCNPX code using the INCL4-ABLA physics models. Cross section data for neutron, proton and deuteron induced reactions were retrieved from the literature where available and some neutron cross sections were calculated using the TALYS code. The good agreement between experimental and calculated reaction rates serves as a validation for the computational models used to simulate fast Accelerator Driven Systems.