Electron and ion beam dynamics of the PF-1000 facility were investigated for the first time at its upper energy limit (≈1 MJ) in relation to neutron emission, the pinch's plasma ('target') characteristics and some other parameters with the help of a number of diagnostics with ns temporal resolution. Special attention was paid to the temporal and the spatial cross correlations of different phenomena. Results of these experiments are in favour of a neutron emission model based on ion beam-plasma interaction with three important features: (1) the plasma target is hot and confined during a few 'inertial confinement times'; (2) the ions of the main part of the beam are magnetized and entrapped around the pinch plasma target for a period longer than the characteristic time of the plasma inductive storage system and (3) ion-ion collisions (both fusion collisions, due to head-on impacts and Coulomb collisions) are responsible for neutron emission. Analysis has shown that one of the ways for achieving a future improvement in the neutron yield of the PF-1000 facility may by changing the geometry of the device. It may ensure an increase in both the discharge current and the initial working gas pressure, eventually resulting in the neutron yield boost.

Since the installation of an ITER-like wall, the JET programme has focused on the consolidation of ITER design choices and the preparation for ITER operation, with a specific emphasis given to the bulk tungsten melt experiment, which has been crucial for the final decision on the material choice for the day-one tungsten divertor in ITER. Integrated scenarios have been progressed with the re-establishment of long-pulse, high-confinement H-modes by optimizing the magnetic configuration and the use of ICRH to avoid tungsten impurity accumulation. Stationary discharges with detached divertor conditions and small edge localized modes have been demonstrated by nitrogen seeding. The differences in confinement and pedestal behaviour before and after the ITER-like wall installation have been better characterized towards the development of high fusion yield scenarios in DT. Post-mortem analyses of the plasma-facing components have confirmed the previously reported low fuel retention obtained by gas balance and shown that the pattern of deposition within the divertor has changed significantly with respect to the JET carbon wall campaigns due to the absence of thermally activated chemical erosion of beryllium in contrast to carbon. Transport to remote areas is almost absent and two orders of magnitude less material is found in the divertor.

The results of studies of high-intensity proton beam generation from thin (1–3 μm) solid targets irradiated by 0.35 ps laser pulse of energy up to 15 J and intensity up to 2×1019 W/cm2 are reported. It is shown that the proton beams of terawatt power and intensity around 1018 W/cm2 at the source can be produced when the laser-target interaction conditions approach the skin-layer ponderomotive acceleration requirements. The proton beam parameters remarkably depend on the target structure and can be significantly increased with the use of a double-layer Au/PS target (plastic covered by 0.1–0.2 μm Au front layer).

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