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A synthetic fast-ion loss (FIL) detector and an imaging Heavy Ion Beam Probe (i-HIBP) have been implemented in the 3D hybrid kinetic-magnetohydrodynamic code MEGA. First synthetic measurements from these two diagnostics have been obtained for neutral beam injection-driven Alfvén Eigenmode (AE) simulated with MEGA. The synthetic FILs show a strong correlation with the AE amplitude. This correlation is observed in the phase-space, represented in coordinates (P, E), being toroidal canonical momentum and energy, respectively. FILs and the energy exchange diagrams of the confined population are connected with lines of constant E, a linear combination of E and P. First i-HIBP synthetic signals also have been computed for the simulated AE, showing displacements in the strike line of the order of ∼1 mm, above the expected resolution in the i-HIBP scintillator of ∼100 μm., This work received funding from the European Starting Grant (ERC) from project 3D-FIREFLUC and from the Spanish Ministry of Science under Grant No. FPU19/02267. This work has been carried out within the framework of the EUROfusion Consortium and has received funding from the Euratom research and training programme 2014-2018 and 2019-2020 under grant agreement No 633053. The views and opinions expressed herein do not necessarily reflect those of the European Commission.

The energy straggling of heavy ion beams at tandem energies, passing through thin foils, has been studied with ions of mass up to A = 35. Charge exchange in the foils has been found to have a considerable effect on the energy spread. Thickness non-uniformities in the foils can also make significant contributions. Extrapolation of the observations to the case of a uniform carbon stripper foil in a tandem accelerator suggests energy straggling of the order a few tenths per cent of the beam energy. However, large non-uniformities in the foil could appreciably worsen the beam resolution.

The design and the performance of the Ionization Beam Profile Monitor (IBPM) operating on the residual gas ionization principle are described. The main advantage of the constructed device is the non-contact measuring method. Operating under hard environmental conditions it delivers the information about the primary beam position, profile and intensity in “on-line” regime. It was tested under high gamma and neutron radiation conditions and changing vacuum using a range of low and intermediate energy beams at the beam current of a few nA to 15 μA. The diagnostic box was located in the vicinity of the accelerator, where the neutron flux was over 106 n/cm2s. It was found out that the device is capable to operate in vacuum in the range of 10-6÷10-3 mbar without the loss of the resolution power at the beam current as low as a few nA. The IBPM is prospective for beam profile monitoring due to long time. Emergency situations do not lead to decrease of its operability.