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In 2016, Laboratori Nazionali di Legnaro (Italy) started the commissioning of a new accelerator facility based on a high-power cyclotron able to deliver proton beams up to 70 MeV of energy and 700 $\mu$A current. Such a machine is the core of the Selective Production of Exotic Species (SPES) project whose main goal is to provide exotics beam for nuclear and astrophysics research and to deliver high-intensity proton beams for medical applications and neutrons generator.

A Low Energy Beam Transport (LEBT) has been designed and optimized to inject both a 50keV/u, 50mA $H^{+}$ beam and a 20keV/u, 1mA ${}^3{\mathrm{\text{He}}}^{2+}$ beam into the downstream Radio Frequency Quadrupole (RFQ) at the Lanzhou Light Ion Cancer Therapy Facility (LLICTF). The overall aim is to increase the operation efficiency and simplify the complexity of the LLICTF. This dual-beam operation mode creates phase space distortions as a result of the intense space charge, and causes transverse asymmetry due to a mixture of solenoids and a dipole magnet. To mitigate the phase space distortions of the high-intensity proton beam, two beam scrapers have been placed at locations determined through careful analysis of the space charge forces and external focusing force of the beam. Additionally, the Particle Swarm Optimization (PSO) algorithm has been utilized to obtain an approximate solution for the dipole parameters, which helps maintain the symmetry of different symmetrical beams passing through it. Optics designs that implement these solutions are verified with multi-particle simulations.

The purpose of this study was to investigate the how seat order in a two-seater (K2) crew boat could influence the performance time and stroke synchronization during high intensity sprint kayaking. Sixteen national team sprint kayakers formed eight K2 crews based on preference. Each crew performed two 200m segments at high intensity in their preferred order (e.g., Paddler A in front, Paddler B behind), and then the reversed order (i.e., Paddler B in front, Paddler A behind). Video analysis identified stroke synchronization based on a four-position model. Magnitude-based inferences were used for statistical analysis. The preferred seat order was $0.5\pm 1.8$s faster than the reversed seat order but the effect was possibly trivial. As four crews were faster in the reversed seat order, data were also rearranged to compare between the slower and faster trials. The faster trials were $1.5\pm 0.5$s quicker than the slower trials, which was a very likely effect. There was no clear effect of seat order on stroke synchronization between the two paddlers. Since faster timing does not always correspond with the preferred sear order, sprint kayak athletes are recommended to try both possible seat orders in a K2 crew boat rather than relying on preference alone.

Charge strippers play a critical role in many high intensity heavy ion accelerators. Here we present some history of recent stripper technology development and indicate the capabilities and limitations of the various approaches. The properties of solid, gaseous, and liquid strippers are covered. In particular, the limitations of solid strippers for high intensity, high atomic number heavy ions and the unique features of helium gas and liquid lithium for high intensity applications are covered. The need for high quality simulation of stripper performance as important input for system optimization is explained and examples of the current simulation codes are given.

The idea of using accelerators in the production of energy by inertial confinement fusion has been developed since the mid-1970s. The basic concept is to use accelerated beams of heavy ions to provide energy to implode and ignite a small fusion pellet. Accelerators have been seen as attractive for this application due to their reliability, high repetition rate, and potential efficiency. They are therefore competitive with high power lasers at least for the commercial production of electrical power. This review summarizes part of the development and scientific efforts directed toward this application, which has been realized over time to be an extremely demanding one. Here we focus primarily on the rf linac/storage ring driver system approach and summarize the specific development that culminated in the European HIDIF study of the late 1990s. We also discuss some of the relevant followup accelerator studies.

Intense laser light at facilities such as the Extreme Light Infrastructure and the European X-ray Free Electron Laser offer new prospects for probing fundamental physics. Here we examine the theory behind QED processes in background fields modelling ultra-strong, short-duration laser pulses. We focus on pair creation via the trident and photon-stimulated mechanisms.

The idea of using accelerators in the production of energy by inertial confinement fusion has been developed since the mid-1970s. The basic concept is to use accelerated beams of heavy ions to provide energy to implode and ignite a small fusion pellet. Accelerators have been seen as attractive for this application due to their reliability, high repetition rate, and potential efficiency. They are therefore competitive with high power lasers at least for the commercial production of electrical power. This review summarizes part of the development and scientific efforts directed toward this application, which has been realized over time to be an extremely demanding one. Here we focus primarily on the rf linac/storage ring driver system approach and summarize the specific development that culminated in the European HIDIF study of the late 1990s. We also discuss some of the relevant followup accelerator studies.

MIT-Bates, in collaboration with BNL, has developed a high intensity polarized electron gun for the eRHIC project. The gun implements large area cathode, ring-shaped beam and active cathode cooling. The paper describes the current status of the project.

Charge strippers play a critical role in many high intensity heavy ion accelerators. Here we present some history of recent stripper technology development and indicate the capabilities and limitations of the various approaches. The properties of solid, gaseous, and liquid strippers are covered. In particular, the limitations of solid strippers for high intensity, high atomic number heavy ions and the unique features of helium gas and liquid lithium for high intensity applications are covered. The need for high quality simulation of stripper performance as important input for system optimization is explained and examples of the current simulation codes are given.