In this paper we analyze from the technical point of view the possibility of developing the IFMIF facility (International Fusion Materials Irradiation Facility) in a stepped approach from the prototypes, presently under testing in the framework of the IFMIF/EVEDA Project (IFMIF Engineering Validation and Engineering Design Activities), but with the capability to fulfill the DEMO (Demonstration reactors) needs in a first step and the fusion power plant needs in a second step. The paper is focused on the so-called DONES (DEMO Oriented Neutron Source) alternative. It is built using one of the 40 MeV IFMIF accelerators, together with a strong simplification of some of the other systems and subsystems, driven by the lower power to be handled in the DONES facility, by transferring the PIE (post-irradiation experiment) analysis to other external facilities, by reducing the remote handling activities foreseen in the facility, and by reducing the type of irradiation experiments to be performed simultaneous...

The N(⁴S_u)+NO(X ²Π)→N₂(X ¹Σ_g⁺)+O(³P_g) reaction plays an important role in the upper atmosphere chemistry and as a calibration system for discharge flow systems. Surprisingly, very little theoretical and experimental work has been devoted to the characterization of the dynamical features of this system. In this work a Sorbie–Murrell expression for the lowest ³A‘ potential energy surface (PES) connecting reactants in their ground electronic states based upon the fitting of an accurate ab initio CI grid of points has been derived. The PES fitted shows no barrier to reaction with respect to the reactants asymptote in accordance with experimental findings and becomes highly repulsive as the NNO angle is varied away from the saddle point geometry. The results of preliminary quasiclassical trajectory calculations on this surface reproduce very well the experimental energy disposal in products, even though the vibrational distribution derived from trajectories seems to be a bit cooler than the experimental data. Moreover, thermal rate constants derived from trajectories are in excellent accordance with experimental values.

The IFMIF-DONES (International Fusion Material Irradiation Facility-DEMO Oriented NEutron Source) facility is being designed with the general objective of providing irradiation of representative samples of power fusion machine materials under prototypical conditions. A linear accelerator will deliver deuterons at high intensity to circulating lithium in a loop, which will produce neutrons capable of obtaining the required damage conditions. As a result of this process, radionuclides will be produced as a by-product, which is characterized by several degrees of mobility. Shielding and radiation protection measures will be required in the facility. IFMIF-DONES will be classified as a first class radioactive facility according to national regulations, with Spain being the European candidate to site the facility. Several aspects of the main safety instructions affecting the facility’s design are explained and discussed in this paper.