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The state‐of‐the‐art mixed‐halide perovskite (MHP) quantum dots (QDs) open up promising applications in photovoltaic and optoelectronic communities, yet are limited by huge halide segregation. In contrast to the previous A‐site alloy method, customizing other octahedral units for replacing the fundamental optoelectronic unit of [PbX6]4− (X = Cl, Br, or I), the so‐called B‐site alloying strategy, is expected to inhibit halide segregation fully. Here, a halide octahedron alloying reconstruction engineering is reported to fabricate MHP QDs with near‐zero halide segregation due to their strongly confined excitons. This unprecedented regime is obtained at a water–oil interfacial reaction system using amino‐silane ion exchange accelerator and transition metal hydroxy‐halides salts, introducing abundant [MX6]4− (M = Zn, Ni, Co, Mn, and Cu) octahedron block and finally fabricating transition metal‐alloyed MAPbX3 QDs. Photo‐induced excitons in strongly dielectric‐confined Zn‐alloyed perovskite QDs are hardly thermally dissociated and transferred, as featured by ultra‐high exciton binding energy (Eb), fast fluorescence lifetimes (τavg), and near 100% photoluminescence quantum yield (PLQY). The fabricated mixed‐halide MAPb1‐xZnxX3 QDs with reduced Pb content over 40% exhibit near‐zero halide segregation, marking the emergence of a practical solution to the detrimental segregation problem, which paves the wave for emerging solar cells and lighting display applications. [ABSTRACT FROM AUTHOR]

The production of light, energetic and low-flux ions as a secondary beam caused by nuclear reaction can be used in various branches of nuclear physics. Due to the limited availability of energy in small laboratories equipped with electrostatic accelerators, accessing energetic light particles is crucial. For this purpose, selected nuclear reactions were introduced. In this research, primary proton, deuterium and helium-3 beams with energy less than 2 MeV were used for samples with a thickness of 1019 atom.cm-2 and the yield of reactions was obtained. The laboratory setup was designed in such a way that in addition to the access to the nuclear reaction products with a suitable yield, favorable conditions were provided for the extraction and transfer of the reaction products as well as their interaction with the sample. In these exothermic nuclear reactions, the yield is in the order of 106 particles and secondary proton and alpha particles with energies of 4 to18.5 MeV have been obtained. Also, the selected reactions are in accordance with the radiation protection protocols of similar laboratories. [ABSTRACT FROM AUTHOR]

Low‐temperature rechargeable aqueous zinc metal batteries (AZMBs) as highly promising candidates for energy storage are largely hindered by huge desolvation energy barriers and depressive Zn2+ migration kinetics. In this work, a superfast zincophilic ion conductor of layered zinc silicate nanosheet (LZS) is constructed on a metallic Zn surface, as an artificial layer and ion diffusion accelerator. The experimental and simulation results reveal the zincophilic ability and layer structure of LZS not only promote the desolvation kinetics of [Zn(H2O)6]2+ but also accelerate the Zn2+ transport kinetics across the anode/electrolyte interface, guiding uniform Zn deposition. Benefiting from these features, the LZS‐modified Zn anodes showcase long‐time stability (over 3300 h) and high Coulombic efficiency with ≈99.8% at 2 mA cm−2, respectively. Even reducing the environment temperature down to 0 °C, ultralong cycling stability up to 3600 h and a distinguished rate performance are realized. Consequently, the assembled Zn@LZS//V2O5‐x full cells deliver superior cyclic stability (344.5 mAh g−1 after 200 cycles at 1 A g−1) and rate capability (285.3 mAh g−1 at 10 A g−1) together with a low self‐discharge rate, highlighting the bright future of low‐temperature AZMBs. [ABSTRACT FROM AUTHOR]

In this work, two types of nanoporous alumina membranes were prepared and tested. Structural features of the samples obtained by using different acids were investigated by scanning electron microscopy (SEM). And further SEM-images were analyzed by different types of fractal dimension estimation methods. The transmission and scattering of accelerated He+ ions were studied in experiments on the ion irradiation of dielectric channels based on porous alumina. An ion accelerator was used as a source of the He+ beam with an energy of 1.7 MeV. Ion scattering was studied by Rutherford backscattering spectrometry. Helium transition through nanoporous alumina at various angles between the normal to the sample and the beam direction were observed. It is shown that the porous structure of anodic aluminum oxide is excellent as a dielectric matrix of nanocapillaries. Owing to the small angle scattering, it allows for the transportation of the accelerated charged particles through the dielectric capillaries, and, as a result, the localization of high energy ion irradiation effects. Additionally, according to the transmission of UV–V is spectra, the energy gaps of samples obtained were calculated. [ABSTRACT FROM AUTHOR]

Collisionless shock waves are efficient ion accelerators. Previous numerical and observational studies have shown that quasi‐parallel (Q‖) shocks are more effective than quasi‐perpendicular (Q⊥) shocks at generating energetic ions under steady upstream conditions. Here, we use a local, 2D, hybrid particle‐in‐cell model to investigate how ion acceleration at super‐critical Q⊥ shocks is modulated when tangential discontinuities (TDs) with large magnetic shear are present in the upstream plasma. We show that such TDs can significantly increase the ion acceleration efficiency of 2D Q⊥ shocks, up to a level comparable to Q‖ shocks. Using data from the hybrid model and test particle simulations, we show that the enhanced energization is related to the magnetic field change associated with the discontinuity. When shock‐reflected ions cross the TD during their upstream gyromotion, the sharp field change causes the ions to propagate further upstream, and gain additional energy from the convection electric field associated with the upstream plasma flow. Our findings illustrate that the presence of upstream discontinuities can lead to bursts of energetic ions, even when they do not trigger the formation of foreshock transients. These results emphasize the importance of time‐variable upstream conditions when considering ion energization at shocks. Key Points: Bursts of energetic ions can appear upstream of quasi‐perpendicular shocks due to highly sheared upstream tangential discontinuitiesThe magnetic field change of the discontinuity enables the shock‐reflected ions to be further energized by the convection electric fieldThis process results in a local acceleration efficiency comparable to that of quasi‐parallel shocks under steady upstream conditions [ABSTRACT FROM AUTHOR]

Bismuth-antimony alloys are among the most studied topological insulators and also have very promising thermoelectric properties. In addition, in the amorphous state they exhibit superconductivity with critical temperatures in the range 6.0–6.4 K. In this work, we have prepared and studied different polycrystalline films of B i 100 – x S b x (x = 0, 5, 10, 15), and we have induced, through ion beam irradiation, significant damage in their internal structure with the aim of amorphizing the material. Specifically, we have irradiated Bi ions in the 10–30 MeV range, exploiting the capabilities of a 5 MV ion beam accelerator of tandem type. We have characterized the Bi–Sb films before and after irradiation from a morphological and structural point of view and measured their electrical resistivity from room temperature to near 2 K, to evaluate the influence of the preparation method and degree of disorder. We have found that the studied Bi–Sb system always behaves as a small energy gap semiconductor that follows the empirical Meyer–Neldel rule, which correlates the conductivity prefactor with the exponential value of the energy gap. [ABSTRACT FROM AUTHOR]

Polyimide films of thickness 7.5 µm are irradiated by a wide range of ions (1H to 197Au) with energies between 1.05 and 48 MeV. Irradiated samples are then chemically etched in sodium hypochlorite solution to investigate nanopore formation due to ion track etching. A threshold in terms of electronic stopping power, Set, needs to be surpassed to preferentially etch the ion tracks. Close to Set, intermittent tracks are formed where only part of the track is etchable. The fraction of these etchable parts increases as we move away from Set, toward higher stopping powers, eventually yielding continuous etchable tracks. Both intermittent and continuous track formation thresholds are observed to be velocity‐dependent, yielding a decrease of the thresholds in the present work compared to previously reported thresholds for swift heavy ions. This finding leads the authors to suggest that electrostatic ion accelerators with terminal voltages of several MV are applicable for the production of ion track membranes up to ≈10–20 µm in thickness. Suitable ions for nanopores in 7.5 µm polyimide films include 42 MeV 59Co and 48 MeV 197Au. The growth mechanism for the pores during etching is discussed, relating it to the properties of the original ion track. [ABSTRACT FROM AUTHOR]

Radiation hardening is studied for stainless austenitic and ferritic-martensitic chromium steels after ion and neutron irradiation at various temperatures. Austenitic and ferritic-martensitic steels irradiated up to 30 dpa in various nuclear reactors and ion accelerators are studied at various temperatures. A change in Vickers microhardness is used as the radiation hardening parameter. A methodology is developed that allows one to determine the ion irradiation parameters, which ensure the radiation hardening of ferritic-martensitic and austenitic steels, as close as possible to the radiation hardening of the same steels under neutron irradiation. A transferability function is introduced to connect the irradiation temperatures for ion and neutron irradiation that provides the same radiation hardening. On the basis of the obtained experimental data, after ion and neutron irradiation the transferability functions are determined for the investigated austenitic and ferritic-martensitic steels, which connect the temperatures for ion and neutron irradiation and provide the same radiation hardening at a given damage dose. [ABSTRACT FROM AUTHOR]

Radio‐photovoltaic cell is a micro nuclear battery for devices operating in extreme environments, which converts the decay energy of a radioisotope into electric energy by using a phosphor and a photovoltaic converter. Many phosphors with high light yield and good environmental stability have been developed, but the performance of radio‐photovoltaic cells remains far behind expectations in terms of power density and power conversion efficiency, because of the poor photoelectric conversion efficiency of traditional photovoltaic converters under low‐light conditions. This paper reports an radio‐photovoltaic cell based on an intrinsically stable formamidinium‐cesium perovskite photovoltaic converter exhibiting a wide light wavelength response from 300 to 800 nm, high open‐circuit voltage (VOC), and remarkable efficiency at low‐light intensity. When a He ions accelerator is adopted as a mimicked α radioisotope source with an equivalent activity of 0.83 mCi cm−2, the formamidinium‐cesium perovskite radio‐photovoltaic cell achieves a VOC of 0.498 V, a short‐circuit current (JSC) of 423.94 nA cm−2, and a remarkable power conversion efficiency of 0.886%, which is 6.6 times that of the Si reference radio‐photovoltaic cell, as well as the highest among all radio‐photovoltaic cells reported so far. This work provides a theoretical basis for enhancing the performance of radio‐photovoltaic cells. [ABSTRACT FROM AUTHOR]

The theoretical possibilities of increasing the resolution and sensitivity of a time-of-flight mass spectrometer with orthogonal ion injection are considered. The effects are achieved by using inhomogeneous electrostatic fields of special configurations both in the accelerating and focusing parts of the device – a cylindrical immersion objective and a transaxial mirror, respectively. It is shown that the use of an inhomogeneous cylindrical field of a special configuration as an ion accelerator opens up the possibility of a multiple reduction in the energy spread of ions in injected ion packets, associated with the so-called "turnaround time" and, therefore, a significant (two or more times) increase in the limiting resolution of the mass spectrometer. The use of a transaxial electrostatic mirror as a time-of-flight mass analyzer makes it possible to significantly increase the sensitivity of the mass-spectrometer due to the implementation of triple spacetime-of-flight focusing of ion packets. Key features include reduced ion energy spread, increased maximum resolution, and improved sensitivity due to triple focusing in space and time of flight. This research lays the foundation for expanding the capabilities of time-of-flight mass spectrometry, providing a more efficient and powerful tool for a wide range of scientific and industrial applications. The effects are achieved by using inhomogeneous electrostatic fields of a special configuration in both the accelerating and focusing parts of the device – a cylindrical immersion lens and a transaxial mirror, respectively. Numerical calculations of the system – a four-electrode cylindrical immersion lens in combination with a three-electrode transaxial mirror – are presented, which confirm the conclusions of the theory [ABSTRACT FROM AUTHOR]

In the framework of the JINR scientific program on study of hot and dense baryonic matter a new accelerator complex Ion Collider fAcility (NICA) based on the Nuclotron-M is under realization. It will operate at a luminosity up to cm s for ions up to Au79+. Two interaction points are foreseen at NICA for two detectors which will operate simultaneously. One of these detectors, the Multi-Purpose Detector (MPD), is optimized for investigations of heavy-ion collisions. The Time-Projection Chamber (TPC) is a well-known detector for 3-dimensional tracking and particle identification for high multiplicity events. The conceptual layout of MPD, TPC design and its parameters, the current status of the readout based on multiwire proportional chamber (MWPC) and readout electronics based on SAMPA chip as well as the status of TPC subsystems are presented. [ABSTRACT FROM AUTHOR]

In this Tutorial, surface and double charge exchange negative ion sources for producing negative ion beams of different ion species will be described. The need for negative ions as the beam particles of tandem Van de Graaf accelerators and that for charge exchange injection of hydrogen negative ions into high-energy proton accelerators requires the development of these ion sources, which are then enlarged to generate ampere level broad beams to heat up, after neutralization, the fusion experiment plasmas confined in magnetic field. The physical mechanisms leading to the formation of various negative ion species, such as hydrogen, helium, alkali metals, and halogens will be presented, and the ion source designs are analyzed based on the knowledge of fundamental processes related to negative ion formation and destruction. The use of negative ion sources in accelerators, nuclear fusion research, technology, and medicine will also be presented. [ABSTRACT FROM AUTHOR]

This paper presents the results of the development and testing of a secondary ion accelerator for the diagnostic complex of neutral particle analyzers at ITER. The accelerator is part of an analyzer designed to measure fluxes of neutral deuterium and tritium particles escaping from reactor plasma in a total range of 10–200 keV. The aim of the accelerator is to improve the signal/background ratio of the analyzer. It is especially important for the region with a relatively low energy of 10–50 keV. The accelerator has the function of converting atoms into secondary ions and accelerating them in an electrostatic field with a voltage of up to +100 kV. The accelerator is based on two high-voltage accelerating tubes. A special unit is built into the central electrode of the accelerator, which provides the replacement of stripping foils used for the conversion of the flux of neutral particles into a flux of secondary ions. The high-voltage tube assembly is encompassed by a sealed steel housing, in which electrical insulation is provided by a gas gap (nitrogen at 6 bar). The results of tests of the accelerator under ITER relevant conditions, namely, under high-intensity gamma irradiation and seismic loads, have shown its high reliability for use in the diagnostic complex of the fusion reactor. [ABSTRACT FROM AUTHOR]

The Streaked Optical Pyrometer (SOP) is a visible diagnostic widely used to study the warm dense matter regime at high energy laser facilities, gas guns, or ion accelerators. It is usually coupled with a Velocity Interferometer System for Any Reflector (VISAR) diagnostic for simultaneous shock wave velocity, reflectivity, and temperature measurements to study the Equation of State (EOS) of materials. While VISAR is a well-mastered technology that provides velocity measurements with low relative uncertainties (close to percent), SOP diagnostics still suffer from high imprecision. In this article, we present a new calibration method in order to obtain absolute temperature measurements with reduced uncertainties. This approach is based on a novel light source: a Ce:YAG luminescent concentrator pumped by LEDs. This device produces enough optical power for calibration at the nanosecond sweep duration of the streak camera. As a demonstration, it has first been installed at the LULI facility and tested on quartz samples shocked at temperatures above 4000 K. [ABSTRACT FROM AUTHOR]

The SORGENTINA-RF project aims at developing a 14 MeV neutron source based on a deuterium/tritium ion accelerator and a rotating target where fusion reactions take place. Among the different research fields, the most interesting and promising is medical radioisotope production. In this framework, intense research work on the design of the rotating target has been carried out. More in detail, to define the optimal design configuration, a sensitivity analysis on the mechanical performance of the rotating target considering the influence of some relevant parameters, such as material type, thickness, and presence of internal stiffeners, was carried out. Among the materials analyzed, aluminium alloy represents the best compromise to efficiently address all the critical requirements in the design phase. One of the most demanding project requirements that the conceptual design must fulfill is the ability of the target to dissipate a thermal power of 250 kW without precluding its mechanical properties and resistance. To investigate the performance of the rotating target, some thermo-mechanical analyses were undertaken with finite element method under some thermal transients and mechanical loads able to simulate the working conditions of the system. The numerical results emphasise the target's ability to withstand operating conditions. The main outcomes of the present study have been implemented as engineering solutions in the project design. [ABSTRACT FROM AUTHOR]

Numerous ambitious particle accelerator facilities, based on proton and ion linear accelerators, have recently been in development for fundamental research, as well as for industrial applications. The advanced design of such new machines, as well as the upgrade and optimization of existing linacs, requires adequate, precise and reliable tools to simulate beam dynamics. The software package DYNAMION, created about 30 years ago, is undergoing systematic improvement and further development in order to characterize modern ion linacs and to provide solutions for its intrinsic complex problems. The DYNAMION code features Front to End beam dynamics simulations under space charge conditions in a linac system, comprising an arbitrary sequence of accelerating-focusing structures and beam transport lines. The evolution of a macroparticle ensemble could be analyzed at a high level of specification. A 3D distribution of the external electrical field (RFQ, DTL) is modeled using integrated internal solvers. Optionally, a 3D electromagnetic field mapping, supplied by specialized external codes, could be used. The recent status of the DYNAMION software package is presented in this paper. Furthermore, the performance of the code is demonstrated on the basis of its application for various linear accelerator/decelerator projects. [ABSTRACT FROM AUTHOR]

Aqueous zinc‐iodine (Zn‐I2) batteries are promising candidates for grid‐scale energy storage due to their safety and cost‐effectiveness. However, the shuttle effect of polyiodides, Zn corrosion, and accumulation of by‐products restrict their applications. Herein, a simple vermiculite nanosheets (VS) suspension electrolyte is designed for simultaneous confinement of polyiodides and stabilization of Zn anode. It is found that the generation of I5− as dominant intermediate and the precipitation reaction between I5− and alkaline by‐products should cause irreversible iodine species loss. Benefiting from the high binding energy between polyiodides and silica‐oxygen bonds of VS, dissolved polyiodides are effectively anchored on the surface of VS suspended in the bulk electrolyte to suppress the shuttle effect, which is confirmed by in situ Raman, Ultraviolet‐visible characterizations and theoretical calculations. Furthermore, the self‐assembly VS interfacial layer on the surface of Zn anode hinders side reactions induced by polyiodides. Meanwhile, the interlayer and surface excess negative charges of VS tend to be compensated by Zn2+ from diffuse layer, which serves as ion accelerators for transferring Zn2+ at the interface immediately, rendering dendrite‐free Zn plating/stripping behavior. Consequently, the Zn‐I2 battery with VS electrolyte achieves an ultra‐long lifespan of 40000 cycles with a negligible capacity decay at 20 C. [ABSTRACT FROM AUTHOR]

High Voltage Engineering developed, built, and tested a unique 2 MV single-ended accelerator (SingletronTM) for light ions. The system combines a beam current of up to 2 mA for protons and helium in direct-current mode with nanosecond-pulsing capability. Compared to other chopper-buncher applications with Tandem accelerators, the single-ended accelerator increases the charge per bunch by about a factor of 8. The all-solid-state Singletron 2 MV power supplyTM supports high-current operation and features a large dynamic range of the terminal voltage and good transient performance to support the high-current operation. The terminal accommodates an in-house developed 2.45 GHz electron cyclotron resonance ion source and a chopping-bunching system. The latter features phase-locked loop stabilization and temperature compensation of the excitation voltage and its phase. The chopping bunching system further features the selection of hydrogen, deuterium, and helium as well as a pulse repetition rate, ranging from 125 kHz to 4 MHz, that are fully computer controlled. In the testing phase, the system demonstrated smooth operation for 2 mA proton and helium beams at terminal voltages from 0.5 to 2.0 MV, and somewhat reduced current at a voltage down to 250 kV. In pulsing mode, pulses with a full width at half maximum of 2.0 ns reached a peak current of ∼10 and ∼5.0 mA for protons and helium, respectively. This is equivalent to a pulse charge of about 20 and 10 pC. Applications range from various fields requiring direct current at multi-mA levels and MV light ions, including nuclear astrophysics research, boron neutron capture therapy, and deep implantation for semiconductor applications. [ABSTRACT FROM AUTHOR]

Enhancing the energy and controlling the divergence of proton beam have been crucial tasks since the development of laser-based ion accelerators. In this study, we employ 2D particle-in-cell EPOCH simulation to investigate a method to control the divergence and enhance the energy of MeV proton beam produced from the interaction of high intensity laser with a gold target. The energy and divergence of proton beam for the conventional laser-foil target configuration are compared with our proposed three laser-three target configuration. In the single laser-single target configuration, a high intensity laser irradiates a gold foil target resulting in proton acceleration from the plasma. In contrast, in the three laser-three target configuration, the generated proton beam is allowed to traverse through the configuration of two parallel Al plates irradiated with high intensity lasers. The new configuration provides the proton energy enhancements of 40% and more collimated beam compared to the single laser-foil target setup. This collimation and energy increase are due to the vertical and horizontal components of the electric field generated by the hot electron plasma of Al plates. The proton energy and divergence can also be tuned by varying the plasma electron density of the Al plasma. Also, the control of proton beam collimation is explored by varying target parameters as well, and it is observed that the separation between the Al plates and length of the Al plates plays major role in controlling the divergence of the beam. This study will have a significant impact in the ongoing laser fusion program, fast ignition, and laser ion therapy. [ABSTRACT FROM AUTHOR]

Hematopoietic tissues of vertebrates are highly radiation sensitive and the effects of ionizing radiation on the hematopoiesis have been studied in mammals and teleosts for decades. In this study, radiation responses in the kidney, the main hematopoietic organ in teleosts, were investigated in Japanese medaka (Oryzias latipes), which has been a model animal and a large body of knowledge has been accumulated in radiation biology. Kidney, the main hematopoietic tissue of adult medaka fish, was locally irradiated using proton and carbon ion beams irradiation system of Takasaki Ion Accelerator for Advanced Radiation Application (TIARA), QST, and the effects on peripheral blood cells and histology of the kidney were investigated. When only kidneys were locally irradiated with proton or carbon ion beam (15 Gy), the hematopoietic cells in the irradiated kidney and cell density in the peripheral blood decreased 7 days after the irradiation in the same manner as after the whole-body irradiation with γ-rays (15 Gy). These results demonstrate that direct irradiation of the hematopoietic cells in the kidney induced cell death and/or cell cycle arrest and stopped the supply of erythroid cells. Then, the cell density in the peripheral blood recovered to the control level within 4 days and 7 days after the γ-ray and proton beam irradiation (15 Gy), respectively, while the cell density in the peripheral blood did not recover after the carbon ion beam irradiation (15 Gy). The hematopoietic cells in the irradiated kidneys temporarily decreased and recovered to the control level within 21 days after the γ-ray or proton beam irradiation (15 Gy), while it did not recover after the carbon ion beam irradiation (15 Gy). In contrast, the recovery of the cell density in the peripheral blood delayed when anemic medaka were irradiated 1 day after the administration of phenylhydrazine. With and without γ-ray irradiation, a large number of hematopoietic cells was still proliferating in the kidney 7 days after the anemia induction. The results obtained strongly suggest that the hematopoietic stem cells in medaka kidney prioritize to proliferate and increase peripheral blood cells to eliminate anemia, even when they are damaged by high-dose irradiation. [ABSTRACT FROM AUTHOR]

A two-dimensional beam monitoring detector named π 2 has been developed and tested at the Bern University Hospital, using an 18 MeV proton beam provided by a medical cyclotron. This non-destructive device utilises a scintillating compound (P47 phosphor) coated onto a thin aluminium foil that is angled at 45 ∘ with respect to the beam axis. The scintillating light produced when the beam passes through the foil is captured by a CMOS camera, resulting in a two-dimensional image of the beam profile. Custom software is then used to analyse the image and extract valuable information about the beam's position, shape, and intensity. The focus of the experimental work was on characterising the performance of the π 2 with the 18 MeV proton beam. The linearity of the detector's output signal was evaluated for proton fluxes ranging from 2 · 10 10 cm − 2 · s − 1 to 5 · 10 11 cm − 2 · s − 1 . Furthermore, the beam profiles measured with the π 2 were found to be consistent with reference measurements obtained using alternative beam monitors. Additionally, the experiments also involved studying the beam scattering caused by the foil and scintillating layer. Finally, in a long-term radiation test, the detector demonstrated a stable response up to an integrated proton flux of 3 · 10 15 cm − 2 . The π 2 is currently being used at the Bern cyclotron for monitoring beams in the development of new methods for medical radioisotope production and for radiation hardness studies. The π 2 has potential applications in several fields that involve the use of accelerated ions, such as cancer particle therapy, medical radioisotope production and radiation hardness studies. [ABSTRACT FROM AUTHOR]

We measure double differential cross sections (DDCS) of electrons emitted from CH4 molecules in collisions with 250 keV protons. The projectile ions are obtained from a 400 kV electron cyclotron resonance-based ion accelerator (ECRIA). We study the energy and angular distributions of the electron DDCS. The observed double and single differential and the total cross section are compared with the state-of-the-art continuum distorted wave eikonal initial state (CDW-EIS) model predictions. Two different approaches are used considering the different target descriptions: complete neglect of differential overlap (CNDO) and molecular orbital (MO) approximations. The MO model uses two different scaling parameters (d = 0.7 and 1.0). In the energy distribution of the DDCS, the carbon KLL Auger line is also observed at 240 eV. The single differential cross section (SDCS) and total cross section (TCS) are derived. Both the MO-based CDW-EIS models are in good agreement with the experimental results; however, the CNDO approach overestimates the data. [ABSTRACT FROM AUTHOR]

Experimental campaigns were undertaken to understand and improve the coupling efficiency of Radio frequency (RF) power into the plasma in three accelerator-based ion sources. Different matching circuit and mechanical engineering setups were used and the network resistance calculated. The efficiency was then measured for a range of RF frequencies and input gas flows. Coupling efficiencies of around 60% were measured in setups using RF-coils mounted external to the plasma chamber. The efficiency is improved to 80% when the coil is immersed in the plasma, allowing closer coupling. As well as the coil geometry, the isolation transformer required for beam production contributes to the overall losses. [ABSTRACT FROM AUTHOR]

An implementation of the tomographic reconstruction of the beam transverse phase space portrait based on fast simultaneous algebraic reconstruction technique, which is rarely used in accelerator physics, is presented. The developed diagnostic procedure has been performed at the INR RAS high-intensity linear accelerator of hydrogen ions and has been experimentally tested in the beam energy range from several tens to several hundred MeV. The applicability of data from different beam-profile monitors is shown, and the tomographic method is compared to the standard transverse profiles method. A procedure for verifying reconstructed data is proposed for use in transfer matrix codes, and examples of its use in case of significantly nonelliptical phase portraits are presented. [ABSTRACT FROM AUTHOR]

Polymer membranes are conventionally prepared using high-energy particles from radioactive decay or by the bombardment of hundreds of MeVs energy ions. In both circumstances, tracks of damage are produced by particles/ions passing through the polymer, and successively, the damaged material is removed by chemical etching to create narrow pores. This process ensures nanosized pore diameter but with random placement, leading to non-uniform local pore density and low membrane porosity, which is necessary to reduce the risk of their overlapping. The present study is focused on the use of polyethylene terephthalate (PET) foils irradiated by 10.0 MeV carbon ions, easily achievable with ordinary ion accelerators. The ion irradiation conditions and the chemical etching conditions were monitored to obtain customized pore locations without pore overlapping in PET. The quality, shape, and size of the pores generated in the micromembranes can have a large impact on their applicability. In this view, the Scanning Transmission Ion Microscopy coupled with a computer code created in our laboratory was implemented to acquire new visual and quantitative insights on fabricated membranes. [ABSTRACT FROM AUTHOR]

NASA's Evolutionary Xenon Thruster (NEXT) is a candidate for future deep space missions that offers high efficiency and specific impulse over a large power throttling range. One of the key life-limiting components is the ion accelerator system, which is subject to sputter erosion by low energy discharge plasma ions incident on the upstream screen grid and higher energy charge exchange ions that impact the downstream accelerator grid. The grid erosion codes CEX2D and CEX3D were validated with data from tests of NEXT as well as the NSTAR ion thruster and then used to assess the time to failure in space due to screen grid erosion and electron backstreaming caused by accelerator grid aperture erosion. Screen grid erosion was found to be important only at the lowest throttle levels, and was conservatively estimated to lead to failure after processing over 900 kg of xenon. The first failure mode at high power levels was found to be electron backstreaming due to accelerator grid hole wall erosion, which would occur after processing over 700 kg of propellant. [ABSTRACT FROM AUTHOR]

A target chamber has been developed and manufactured for carrying out simulation experiments with two simultaneous beams of heavy and light ions. The target chamber is equipped with elements for beam diagnostics and target-temperature control. The chamber allows the installation of plasma cleaning systems and nitrogen trap. [ABSTRACT FROM AUTHOR]

Ion accelerator is а multi-tool used for effects of neutron irradiation of reactor materials simulating. The heavy ion accelerator HIPr (heavy ion prototype) is used for radiation damage in steels and alloys simulating at ITEP (NRC "Kurchatov institute"). The main irradiations is carried out with iron ions Fe2+ but, if necessary, vanadium, tantalum, carbon and many others ions beams can be used. It is necessary to implant hydrogen and helium into the area of damage for effect of nuclear reaction products on reactor structural materials simulating. The second channel is created for simultaneous irradiation with heavy and light ions for improving experiments. The paper considers solenoid design. The solenoid is used to a helium ion beam from ECR source focusing and the method of its power supply. [ABSTRACT FROM AUTHOR]

An accelerator mass spectrometry (AMS) method has been developed to detect 32Si and separate it from its intense isobar 32S. This separation is achieved using a passive absorber cell in front of a gas ionization chamber at an energy of 30 MeV at the 6 MV Tandem accelerator at the Laboratory of Ion Beam Physics (LIP) at the ETH Zurich. Thereby, the background originating from light recoils was identified and minimized. Additionally, the deviation of the position of the observed spectrum from the expected was explained. The new method is currently undergoing characterisations aiming for the half-life measurement of 32Si. [ABSTRACT FROM AUTHOR]

We report the development and performance of a cold target recoil ion momentum spectrometer (COLTRIMS) setup at TIFR, which is built to study various atomic and molecular processes involving the interaction of slow, highly charged ions from an electron cyclotron resonance based ion accelerator. We give a detailed description of the experimental setup, as well as report some initial results on the electron-capture process in collisions of Ar8+ ions with helium and carbon monoxide targets. Here, we present the longitudinal momentum transfer and the sub-shell resolved Q-value spectrum in the case of 2, 4, and 6 keV/u Ar8+ beams in collision with helium. A longitudinal momentum resolution of 0.27 a.u. is achieved in the present system. We also report the state-selective scattering angle distributions for all the collision systems under investigation. We further discuss the fragmentation of the CO2+ molecular ions for different electron capture channels for the 5 keV/u Ar8+ beam. The combination of the COLTRIMS, along with the beam cleaner, the electrostatic deflectors, and the charge state analyzer, is shown to have certain advantages. [ABSTRACT FROM AUTHOR]

The molecular hydride negative ions of mass 129 amu, 127IH 2 −, 127ID− and 128TeH−, have been studied in order better to understand potential backgrounds in AMS measurements of 129I. All three of these ions appear to be stable or, if metastable, to have lifetimes that are sufficiently long to allow at least some of them to reach the high voltage terminal of the accelerator. It is found, however, that these make only a minor contribution to the combined rate of 127I7+ and 128Te7+ ions that pass around the analysing magnet when it is set for 129I7+ detection. The principal contribution comes instead from the injection of 127I− ions into the accelerator along with the 129I− ions, despite the use of a low Cs sputtering energy in the ion source that was intended to eliminate them. This contribution is, however, small and is effectively removed by a Wien filter. In addition, a sample of Woodward iodine, obtained from the University of Arizona, was found to have an 129I/127I ratio of (13.3 ± 0.9) × 10−15. This is the lowest ratio so far reported. In contrast, the batch of Woodward iodine that was being used as an iodine carrier in our laboratory was found to have a much higher ratio of (78.2 ± 2.4) × 10−15. A search for a lower ratio blank failed to find a suitable material. [ABSTRACT FROM AUTHOR]

A 500 kV ion Accelerator based Accelerator Mass Spectrometer (AMS) system was established in 2015 at the Inter-University Accelerator Centre (IUAC), New Delhi, India (14C Lab Code: IUACD) and is being used routinely for 14C, 10Be and 26Al measurements. The AMS System is backed by three automated graphitization equipment (AGE), a carbonate handling system (CHS) in graphitization laboratory and an appropriate clean laboratory for the chemical processing of samples in case of 10Be and 26Al measurements. In view of the increasing demand for 14C based studies, a major portion of the machine time goes into 14C measurements as compared to other isotopes. It is imperative to assess, monitor and establish the consistency of the performance of the AMS measurements over time since its inception. We have evaluated the short- and long-term performance of 14C measurements with the AMS set-up at IUAC, New Delhi, in terms of the reproducibility, accuracy, precision and calculation of random machine error (RME) in a routine laboratory environment using the International Atomic Energy Agency (IAEA) secondary standards (C1-C9) and chemical blanks in each session. A comparison of the analytical figures of merit between the short- & long-term usages of the AMS facility is presented through a statistical approach highlighting the importance of the measurements and evaluation of primary standards, secondary standards, blanks, and replicates in each of the experiments. A comparison of the analytical performances between the initial set-up and later adoption of a modified analytical protocol has also been made. [ABSTRACT FROM AUTHOR]

Laser-driven ion beams have gained considerable attention for their potential use in multidisciplinary research and technology. Preclinical studies into their radiobiological effectiveness have established the prospect of using laser-driven ion beams for radiotherapy. In particular, research into the beneficial effects of ultrahigh instantaneous dose rates is enabled by the high ion bunch charge and uniquely short bunch lengths present for laser-driven ion beams. Such studies require reliable, online dosimetry methods to monitor the bunch charge for every laser shot to ensure that the prescribed dose is accurately applied to the biological sample. In this paper, we present the first successful use of an Integrating Current Transformer (ICT) for laser-driven ion accelerators. This is a noninvasive diagnostic to measure the charge of the accelerated ion bunch. It enables online estimates of the applied dose in radiobiological experiments and facilitates ion beam tuning, in particular, optimization of the laser ion source, and alignment of the proton transport beamline. We present the ICT implementation and the correlation with other diagnostics, such as radiochromic films, a Thomson parabola spectrometer, and a scintillator. [ABSTRACT FROM AUTHOR]

The slow-neutron flux density and the energy distributions of the fast-neutron flux density have been measured using an SDMF-1608SN digital spectrometer−dosimeter in the fields of the PIAF ion accelerator facility of the National Metrology Institute of Germany (PTB). The results of these measurements demonstrate the high accuracy in measuring the energy and the neutron flux density in a wide energy range (from 24 keV to 20 MeV). [ABSTRACT FROM AUTHOR]

An advanced radio-frequency quadrupole (RFQ) ion cooler was developed for accelerator mass spectrometry to use element-selective laser photodetachment and ion-molecule reactions for isobar suppression. The system will be installed as a central part of the new Anion Laser Isobar Separator (ALIS) at the 6 MV AMS system of CologneAMS. The new RFQ design intends to solve the technical challenge of the deceleration and trapping of heavy molecular ion beams with high emittance. Therefore, an elliptical injection electrode was developed to slow down the ions far away from the central entrance aperture. A new and easy-to-manufacture guide-field assembly was developed. For this purpose, diagonally-split cylindrical surface electrodes are capacitively coupled to a core rod that is carrying the RF signal. Consequently, only low DC voltages are needed to create a gradually changing potential in the longitudinal direction. The RFQ and the acceleration electrodes are installed in a self-aligned structure. [ABSTRACT FROM AUTHOR]

External (in-air) Particle Induced Gamma-ray Emission (PIGE) setup of FOlded Tandem Ion Accelerator (FOTIA), Bhabha Atomic Research Centre (BARC) was utilized for determining concentrations of low Z elements (Si, Na, Al and F) in geological samples by a simple and novel sample preparation method using thin Mylar films to pack direct solid samples. Low energy proton beam was utilized and the current-normalized count rates of analytes were obtained using the count rate of tantalum, the beam exit window material. Meticulousness of the method was ascertained by analysing different CRMs and compared with conventional pelletisation method. Proposed method was adopted for elemental analysis in uranium ore samples for possible nuclear forensic applications. [ABSTRACT FROM AUTHOR]

CERN hosted on May 2-6, 2022, the first annual meeting of the H2020 I.FAST project to support innovation in the field of science and technology of particle accelerators. The project has a completely different character from its predecessors in this area of research. It was approved for implementation a year ago by the EC with the highest marks. It is worth looking at why projects such as ARIES, I.FAST and EURO-LABS are so easily accepted. This alleged ease of acceptance is an appearance. Behind the acceptance, in conditions of extremely tough competition, is the excellent organization of the submitting community that has been developed over the years, as well as the perfect, well-thought-out preparation of the material. The author, a participant in the ARIES and other EC projects in the field of particle accelerator science and technology, presents here, on specific examples, his subjective opinions on how to prepare materials for high-output projects for the EC FP. The author hopes that these remarks may be useful in the process of submitting research projects from Poland in international cooperation to the EC in the best possible way. The science and technology of particle accelerators is an excellent area of showing such examples because it is interdisciplinary and includes the following components: building of research infrastructure, applied physics, mechatronics, materials engineering, automation and robotics, electronics, ICT, innovation, cooperation with industry, and social. [ABSTRACT FROM AUTHOR]

A large body of work has been conducted to investigate the embrittlement and degradation of reactor pressure vessel (RPV) steels. This includes experiments on alloys with different compositions, performed in research and test reactors and ion accelerators spanning various temperatures, fluxes, and fluences. In this paper, we perform a critical review of the published experimental data and compile experimentally reported values for dislocation loop size/density, precipitate size/density and yield stress into an easily downloadable format that can be used by both experimentalists and modelers. This thorough experimental review is complemented by a brief review of simulation efforts at atomistic and mesoscopic length scales. This paper highlights key aspects of the behavior of RPV steels under irradiation, identifies gaps or discrepancies in current understandings, and identifies future priority research directions. • Compiles largest database with experimentally reported values for dislocation loop size/density, precipitate size/density, and yield stress. • Articulates a list of data needs formulated by modeling teams. • Provides recommendations on critical experiments that can be done to validate modeling efforts. [ABSTRACT FROM AUTHOR]

Structural materials of the new generation of nuclear reactors, fission as well as fusion, must often cope with high production rates of transmutation helium. Their testing hence requires either a powerful source of fast neutrons or a high-fluence ion-irradiation facility providing sufficient amounts of high-energy helium to investigate its effect on the material. Most ion irradiation studies, however, concentrate on basic effects such as defect evolution or bubble swelling in narrow near-surface regions modified by ion bombardment. Studies on bulk samples with a relatively thick implanted region, which would enable, for instance, micromechanical testing, are underrepresented. This gap might be filled by high-fluence multi-energy ion irradiations modifying several tens of micrometres of the investigated substrate. High-energy ion accelerators providing reasonable currents with energies of tens of MeV are rarely employed in such studies due to their scarcity or considerable beamtime costs. To contribute to this field, this article reports a unique single-beam He implantation experiment aimed at obtaining quasi-uniform displacement damage across >60 μm with the He/dpa ratio roughly one order of magnitude above the typical spallation neutron target irradiation conditions. Some technical aspects of this irradiation experiment, along with recent developments and upgrades at the 6 MV Tandetron accelerator of the Slovak university of technology in Bratislava, are presented. [ABSTRACT FROM AUTHOR]

The exact solution of the Liouville equation expressed in terms of exponential operators can describe the phase space evolution of particle beams in transport lines. In this paper, we generalize the solution of the above equation for the case of beam losses induced by apertures and for particle beams with large spreads in the momentum space. We discuss the applicability of such approach to ion beams produced by high-intensity lasers interacting with critical plasmas, based on the comparison between theoretical findings and measurements. [ABSTRACT FROM AUTHOR]

Particle accelerators throughout the world vary widely in terms of age and availability of advanced noninvasive diagnostics that provide varying levels of detail about the accelerated beams. Beam loss measurements and current monitors are ubiquitous in the accelerator community, they are noninvasive, and they are some of the most important metrics in terms of preventing damage or irradiation of beam pipes and equipment for high-energy machines. However, beam loss and current measurements are difficult to use for feedback tuning because of a lack of a known analytic relationship between scalar loss measurements throughout an accelerator and the hundreds of thousands of parameters that influence the beam and time variation of the beam source itself. In this work, we present a model-independent extremum seeking (ES) controller, which has been implemented for automated tuning and optimization of the Los Alamos Neutron Science Center (LANSCE) linear ion accelerator based only on scalar quantities, such as beam loss or flux measurements. We demonstrate the approach on various accelerator subsystems, including groups of radio frequency (RF) accelerating cavities, quadrupole magnets, bending magnets, and steering magnets. This tool is now available as a use graphical user interface (GUI) in the LANSCE control room, allowing beam physicists to choose arbitrary groups of parameters and beam loss or current monitors for adaptive tuning. [ABSTRACT FROM AUTHOR]

One of the charged-particle accelerators with relatively low energy and relatively high current is the vacuum-insulated tandem accelerator proposed for boron neutron capture therapy and planned for use in a number of other applications requiring a more remote location of the neutron-generating target from the accelerator. In this work, the phase portrait of the ion beam and its dependence on the ion beam current and the strength of the magnetic lens focusing the beam of negative hydrogen ions on the input of the accelerator are measured. It is shown that the modernization of the magnetic lens contributed to the reduction of the spherical aberration of the lens and improved the quality of the negative ion beam. It has been established that the ion beam emittance increases with increasing current, and the space charge affects the phase portrait of the ion beam in the low energy transport path. To compensate for the action of the space charge on the phase portrait of the proton beam, the strength of the magnetic lens is changed. The obtained experimental data indicate that the proton beam can be transported to the site of the planned location of the neutron-generating target without adding focusing elements. [ABSTRACT FROM AUTHOR]

Mars is a dry planet with a history of a warm and wet environment. Hydrogen and oxygen continuously escape from the unmagnetized planet. Although the heavy ion escape rate in the wake region is low due to Mars' obstruction, there are reports of events with bursty and enhanced ion escape. Here, we first find the evidence of the Alfvenic dayside‐produced plasma clouds accelerated by magnetic reconnection, which provides an explanation for the wake bursty mass escape by the observations from the Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft. In the event reported by this study, two types of flux ropes were successively observed in the magnetic reconnection exhaust in the Martian wake. One is generated by the reconnection, while others are produced by dayside boundary instability. The ions convected from the dayside, as well as the local original ions, can both be accelerated to be Alfvenic and expelled in the Martian tail by reconnection. The oxygen escape rate in the reconnection exhaust is estimated to be a quarter of the previous statistical result in the entire wake region. Plain Language Summary: Although current Mars has a very thin atmosphere, it is generally believed that ancient Mars had a thicker atmosphere. Ion escape plays a key role in the Martian atmosphere evolution. The escape rate behind Mars should be low in the wake. However, recent observations find explosive bulk plasma escape processes in this region, which are poorly understood. Based on observations in the Martian tail region by the Mars Atmosphere and Volatile EvolutioN mission, we report observations of helical magnetic structures of different origins during a single crossing of MAVEN's nightside. For the first time, we propose that tail reconnection acts as an accelerator for the ions which are brought from the dayside ionosphere. These ions can speed up in the wake region and get expelled away from Mars. Our research enhances the role of magnetic reconnection on the ion escape process of Mars, compared with the previous understanding. Key Points: Two types of flux ropes are detected in the magnetic reconnection exhaust during a single crossing of the Martian tail current sheetOne rope is likely formed by reconnection while others by dayside boundary instabilityPlasmas are accelerated to be Alfvenic by reconnection in the Martian tail, leading to the bursty oxygen escape in the wake [ABSTRACT FROM AUTHOR]

Fine structured targets are promising in enhancing laser-driven proton acceleration for various applications. Here, we apply 3D-printed microwire-array (MWA) structure to boost the energy conversion efficiency from laser to proton beam. Under irradiation of high contrast femtosecond laser pulse, the MWA target generates over 1.2 × 1012 protons (>1 MeV) with cut-off energies extending to 25 MeV, corresponding to top-end of 8.7% energy conversion efficiency. When comparing to flat foils the efficiency is enhanced by three times, while the cut-off energy is increased by 32%. We find the dependence of proton energy/conversion-efficiency on the spacing of the MWA. The experimental trend is well reproduced by hydrodynamic and Particle-In-Cell simulations, which reveal the modulation of pre-plasma profile induced by laser diffraction within the fine structures. Our work validates the use of 3D-printed micro-structures to produce high efficiency laser-driven particle sources and pointed out the effect in optimizing the experimental conditions. The performance of laser-driven ion accelerators is intimately linked to the structure of the target. Here, laser-proton acceleration from a 3D-printed microwire-array target boosts the conversion efficiency and cut-off energy compared to a flat foil. [ABSTRACT FROM AUTHOR]

This article reports the development, construction, and experimental test of an angle-resolved Thomson parabola (TP) spectrometer for laser-accelerated multi-MeV ion beams in order to distinguish between ionic species with different charge-to-mass ratio. High repetition rate (HHR) compatibility is guaranteed by the use of a microchannel plate (MCP) as active particle detector. The angular resolving power, which is achieved due to an array of entrance pinholes, can be simply adjusted by modifying the geometry of the experiment and/or the pinhole array itself. The analysis procedure allows for different ion traces to cross on the detector plane, which greatly enhances the flexibility and capabilities of the detector. A full characterization of the TP magnetic field is implemented into a relativistic code developed for the trajectory calculation of each pinhole beamlet. We describe the first test of the spectrometer at the 1 PW VEGA 3 laser facility at CLPU, Salamanca (Spain), where up to 15 MeV protons and carbon ions from a 3 μ m laser-irradiated Al foil are detected. [ABSTRACT FROM AUTHOR]