Neutron irradiation-induced shutdown dose rate estimation in EU DEMO divertor.

The EU DEMO fusion reactor, which is part of the EUROfusion PPPT program and the successor to ITER, aims to facilitate the transition of fusion from the science laboratory to industrial use. Its key objective is net energy production. Its critical component, the divertor, manages power exhaust, ash, and helium removal. The key elements of the divertor include Plasma Facing Components (PFCs), shielding liners, reflector plates, divertor cassettes, and a vacuum vessel locking system. It is imperative that the shutdown dose rates are assessed to ensure workers' radiation protection during maintenance, plan the disposal of radioactive material, and ensure the overall safety of the plant. The shutdown dose rate tool employed in the present study is R2Smesh, which couples MCNP for radiation transport and FISPACT for neutron activation to calculate neutron-induced shutdown dose rates, utilizing an advanced, semi-heterogeneous EU DEMO divertor model, presenting a challenging task in neutron transport calculations.

Activation analysis and evaluation of the radionuclide inventories, decay heat for European DEMO divertor components.

This work presents neutron flux calculation results and specific decay heat and activity for the European DEMO reactor divertor structure. Two DEMO 2017 models were used in calculations; one with a homogenised WCLL breeder blanket and the other with a homogenised HCPB breeder blanket. The neutron flux calculations were performed using MCNP6 code with JEFF 3.2 nuclear data. Activation and decay heat calculations were performed using the FISPACT-II code with TENDL - 2017 nuclear data library.

Dose rates and specific activities of Li2CO3 pellets and diamond detectors irradiated during TT and DTE2 campaigns at JET.

TT and DTE2 campaigns at JET are expected to produce large 14 MeV neutron fluxes that will enable the expansion of activation detection ranges. The calculation results of the activation and dose rates induced in Li2CO3 pellets and diamond detector materials are presented in this research. The MCNP code was used in order to produce corresponding neutron flux densities and spectra. The FISPACT code with the EAF-2010 library was used to estimate the activation and dose rates.