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The National Physical Laboratory has provided industry and academia with fluence, energy, and dose standard neutron fields for characterising neutron detecting instruments since the 1960’s. Sectors such as civil nuclear power, defence, radiation-protection and fusion generation rely on NPLs facilities to innovate, operate safely and ensure traceability back to an internationally recognised UK primary standard. A central part of the capability is the 3.5 MV Van de Graaff accelerator which, using light ions, generates monoenergetic fields of neutrons ranging from a few keV to 20 MeV and intense thermal fields. This accelerator is reaching the end of its operational life and a project to replace it is underway.

An analytical solution to the equation for the distribution of the flux density of reflected light ions over the path length and energy losses in the target is obtained. It is based on the solution of boundary problems for the transport equation using the invariant imbedding method in the small-angle approximation. In the case of proton reflection from copper and tungsten targets, the analytical results are compared with computer-simulation data obtained using the OKSANA program, as well as with experimental data. The possibility of verifying the stopping power of the target material based on the created methodology is noted.

Juno's flyby of Ganymede revealed ion composition in its vicinity with the Jovian Auroral Distributions Experiment–Ion (JADE‐I) instrument. Throughout this flyby, we derive species‐resolved ion density and velocity moments by decomposing the time‐of‐flight data into contributions from individual ion species using species‐dependent fits. At the sub‐Jovian flank magnetopause—a region previously linked to reconnection by previous studies—Juno encountered a strong field‐aligned ion jet. Its direction and magnitude are consistent with Hall‐mediated flank magnetopause reconnection at Ganymede. As reconnection‐accelerated electrons have been associated with Ganymede's polar aurora, the persistence of auroral emission suggests reconnection, and associated ion acceleration may occur along an extended X‐line. These results imply reconnection at Ganymede can act not only as a localized driver of ion jets, but also as a distributed pathway for ion and neutral loss. Given the appropriate reconnection geometry, such a mechanism is likely operating at a broad range of magnetized astrophysical bodies immersed within plasma.

In this paper, the particle acceleration processes around magnetotail dipolarization fronts (DFs) were reviewed. We summarize the spacecraft observations (including Cluster, THEMIS, MMS) and numerical simulations (including MHD, test-particle, hybrid, LSK, PIC) of these processes. Specifically, we (1) introduce the properties of DFs at MHD scale, ion scale, and electron scale, (2) review the properties of suprathermal electrons with particular focus on the pitch-angle distributions, (3) define the particle-acceleration process and distinguish it from the particle-heating process, (4) identify the particle-acceleration process from spacecraft measurements of energy fluxes, and (5) quantify the acceleration efficiency and compare it with other processes in the magnetosphere (e.g., magnetic reconnection and radiation-belt acceleration processes). We focus on both the acceleration of electrons and ions (including light ions and heavy ions). Regarding electron acceleration, we introduce Fermi, betatron, and non-adiabatic acceleration mechanisms; regarding ion acceleration, we present Fermi, betatron, reflection, resonance, and non-adiabatic acceleration mechanisms. We also discuss the unsolved problems and open questions relevant to this topic, and suggest directions for future studies.

The Helium Light Ion Compact Synchrotron (HeLICS) is an innovative synchrotron design for cancer treatment currently under development in the context of the Next Ion Medical Machine Study (NIMMS) at CERN. As part of the lattice design, the beam envelope around the HeLICS circumference is evaluated and the optics functions optimized in order to meet the aperture requirements imposed by the magnet design. Furthermore, the impact of orbit errors arising from magnet misalignments is addressed, taking into account the required margins and tolerances. Correction strategies are proposed to compensate these alignment errors and provide sufficient orbit correction.

The Jovian Auroral Distributions Experiment (JADE) on Juno provides the critical in situ measurements of electrons and ions needed to understand the plasma energy particles and processes that fill the Jovian magnetosphere and ultimately produce its strong aurora. JADE is an instrument suite that includes three essentially identical electron sensors (JADE-Es), a single ion sensor (JADE-I), and a highly capable Electronics Box (EBox) that resides in the Juno Radiation Vault and provides all necessary control, low and high voltages, and computing support for the four sensors. The three JADE-Es are arrayed 120 ∘ apart around the Juno spacecraft to measure complete electron distributions from ∼0.1 to 100 keV and provide detailed electron pitch-angle distributions at a 1 s cadence, independent of spacecraft spin phase. JADE-I measures ions from ∼5 eV to ∼50 keV over an instantaneous field of view of 270 ∘ ×90 ∘ in 4 s and makes observations over all directions in space each 30 s rotation of the Juno spacecraft. JADE-I also provides ion composition measurements from 1 to 50 amu with m /Δ m ∼2.5, which is sufficient to separate the heavy and light ions, as well as O+ vs S+, in the Jovian magnetosphere. All four sensors were extensively tested and calibrated in specialized facilities, ensuring excellent on-orbit observations at Jupiter. This paper documents the JADE design, construction, calibration, and planned science operations, data processing, and data products. Finally, the Appendix describes the Southwest Research Institute [SwRI] electron calibration facility, which was developed and used for all JADE-E calibrations. Collectively, JADE provides remarkably broad and detailed measurements of the Jovian auroral region and magnetospheric plasmas, which will surely revolutionize our understanding of these important and complex regions.

A bstract We perform an analysis of jet quenching in heavy and light ion collisions for scenarios without and with quark-gluon plasma formation in pp collisions. We find that the results for these scenarios are very similar, and both of them are in reasonable agreement with data for heavy ion collisions. However, their results become differ significantly for light nuclei. Using the parameters fitted to heavy ion data on the nuclear modification factor R AA , we make predictions for 0.2 and 7 TeV O+O collisions that can be verified by future experiments at RHIC and the LHC.

Heavy cold ions at Mars are gravitationally bound to the planet unless some process provides energy to them. Observations show that cold (<20 eV) and dense (∼>1 cm−3) O+/O2+ ions with bulk velocities equal to energies ∼1 keV can reach deep into the nightside Martian magnetosheath. These ions are co‐located with a change of the sign of the sunward component of the magnetic field. This magnetic field topology implies the persistence of a localized planetary ions escape channel associated with draped magnetic field lines that are convecting tailward. The observed ion populations propagate approximately in the same direction as surrounding magnetosheath flow and are likely to be almost unheated ionospheric ions from low altitudes. The paper discusses planetary ion energization via Hall electric field originated from ions and electron separation associated with magnetic field curvature. Plain Language Summary In‐situ observations above the nightside of Mars show the presence of localized dense planetary ion fluxes at altitudes exceeding 2,000 km and escaping from the planet at high energies, comparable to that of the solar wind. These fluxes are accompanied by the reversal of sunward component of magnetic field. Unlike most atmospheric escape channels, the reported phenomenon is characterized by an increase in heavy to light ions density ratio with the distance from the planet at the observed altitudes up to nearly 5,000 km, as well as an increase in overall plasma number density inside this escape channel relative to the ambient sheath environment. This behavior is consistent with acceleration process initiated by a bent magnetic flux tube. Key Points Ions of different species gain similar energies in the Martian magnetosheath by Hall electric fields associated with magnetic curvature A high concentration of ionospheric ions correlates with a near void of shocked solar wind protons and a magnetic field reversal Number density at the reversal increases with distance from Mars in comparison to the surrounding sheath at least till two Martian radii

We use intense femtosecond extreme ultraviolet (XUV) pulses with a photon energy of 92 eV from the FLASH free electron laser to irradiate substrate-free CsCl nanoparticles surrounded by a He gas with a number density of around 10 15   cm −3 . By simultaneously detecting electrons and energetic ions from the laser-irradiated micron-size target we study the acceleration mechanism of light ions at the microplasma-vacuum boundary as well as at the layer close to the nanoparticle surface. When the XUV pulse interacts with the gas alone, helium ions are accelerated to energies exceeding 100 eV. In the presence of the nanoparticle, light ions gain additional energy in the electric field around the ionized nanoparticle and their energy spectrum changes considerably. We present an electrostatic model to explain the ion acceleration mechanisms both with and without the nanoparticle and discuss the role of the gas environment in experiments.

This study presents a detailed analysis of longitudinal flow decorrelations in light ion collisions at Relativistic Heavy Ion Collider (RHIC) and Large Hadron Collider (LHC) energies for the first time. We compare different theoretical models of the oxygen structure and find that certain observables such as the flow vector correlator can distinguish between them, particularly highlighting differences between the variational Monte Carlo (VMC) structure and other models, such as Nuclear Lattice Effective Field Theory (NLEFT) and the Projected Generator Coordinate Method (PGCM), which behave similarly. We further examine flow decorrelations across different systems, including d+Au and O+O collisions at 200 GeV, as well as Ne+Ne and O+O collisions at 6.37 TeV, indicating a hierarchy in decorrelations that underscores the complexity of these interactions. Our findings emphasize that the role of asymmetry in d+Au collisions and its impact on flow correlations is mitigated using a modified flow correlation defined as a ratio of two flow vector covariances derived from different pairs of pseudorapidity bins. Additionally, our analysis of flow angle decorrelations shows diverse distributions across various systems, finding distinct patterns in d+Au collisions compared to other collision systems.