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AbstractThe paper describes cross-section measurements consisting of neutron activation using a 7Li(p,n) quasi mono-energetic neutron source and gamma-ray spectrometry performed at the Nuclear Physics Institute of the Czech Academy of Sciences in Řež, Czech Republic. The analysis of the excitation functions of neutron-induced threshold reactions for the energy range from 17 up to 34 MeV is presented. The cross sections for the population of both ground and isomeric states were measured in yttrium and gold. A comprehensive comparison of the measured cross sections with earlier experimental data from the EXFOR database, TALYS calculations, and evaluated nuclear data libraries is presented.

AbstractNeutronic analyses have been performed assessing the performance of the new radiation shielding design of the upper ports in the Neutral Beam (NB) cell of ITER. The scope of the work includes neutron and gamma spectra and nuclear heating calculations inside the port, as well as assessments of fluences, nuclear heating, and insulator radiation doses in the superconductive magnets in the vicinity of the upper port. For radiation transport calculations, the MCNP5 code has been applied with the Alite 4.1 standard 3D model of ITER, in which the inner structure of the upper port was converted from the underlying CAD (CATIA) data. The conversion has been accomplished by means of the McCad interface code. To address human safety issues, maps of shutdown dose rates have been produced using the Rigorous 2 Step (R2S) method enhanced with the mesh-tally capability. The mesh-based R2S approach couples the MCNP5 mesh-tallies with the radioactive inventory results calculated with the FISPACT-2007 activation code allowing automated calculations of shutdown doses including transport of decay gammas. All results satisfy the ITER radiation design requirements.