Ion Beam Generation Research Articles

Service spacecraft for space debris removal

The problem of space debris removal from the near-Earth space is being studied in almost every country taking part in space exploration. This is due to the global threat of critical increase in the number of space debris objects predicted for the near future, in particular as a result of significant growth in demand for multi-satellite constellations for various purposes. To date, researchers have proposed a large number of different methods for space debris removal. The work presented is the development of one of the promising contactless methods of space debris removal by an ion beam. The results of modeling and optimization of physical processes in the ion source to be mounted on board a service spacecraft that is necessary for implementing the considered method of space debris removal are presented. Besides, the results of thermal modeling and thermal mapping of the ion source during its operation are presented also, and the calculation results of its output parameters are compared to experimental data, which verified the small divergence angles of the generated ion beam. To assess the prospects of using a system for contactless space debris transportation by an ion beam using the obtained data on the operating parameters of the ion source, the trajectory design and mission analysis were carried out, which revealed the feasibility of removing seven space debris objects out of the protected region in geostationary orbit by a single service spacecraft. Besides, the preliminary service spacecraft design is presented.

Mass-selected ion beam generation using two rotating electric-field mass separation technique

This paper describes the origin, principles, practical applications, and future perspectives of mass-selected ion beams generated using two rotating electric-field mass (REF-MS) filters. Our team has been investigating the underlying principles of REF-MS separation and assessing the feasibility of developing suitable systems to realize mass separation and ion beam convergence using rotating electric fields as well as the practicability of this method. This paper focuses on the mechanism underlying the observed cycloid trajectories followed by REF-MS-selected ions. A focused ion beam column with Ga and AuGe liquid metal ion sources (LMISs) was connected to REF-MS optics to assess the mass-selection performance of the filter. The mass-separation ability of this system was demonstrated by the ion projection images of Ga-LMIS (69Ga+ and 71Ga+) and AuGe-LMIS (97Au2+, Au2Ge+, and Au2Ge2+). The column was then replaced with a vacuum electrospray ionization (ESI) source. The size-selected water-cluster ion beams [(H2O)nH]+ were separated based on cluster size, and a microscale crater was created. Co-containing molecular ion beams were revealed using different concentrations of ESI sources, and a mass-separated [Co(DEGBE)4]+ ion beam was constructed.

Investigation of intense pulsed ion beam generation by a magnetically insulated ion diode at a reduced impedance

The intense pulsed ion beam (IPIB) generation was investigated at reduced impedance of a magnetically insulated ion diode. The main goal of our research was to obtain IPIB with adjustable parameters at low current densities. The diode impedance was varied by the external magnetic field current by setting the delay of the accelerator's trigger relative to the launch of the magnetic field generator. The B-applied ion diode adjustably generated IPIB with a current density in the range from 25 to 4 A/cm2. In the matched mode the accelerator generates the ion beam with a current density of about 100 A/cm2. Obtained results of the IPIB current density adjustment allows to irradiate samples in a single vacuum cycle without the change of charging voltage of both magnetic field and accelerating voltage generators. Gold films with a thickness of 10 nm deposited on fluorine-doped tin oxide (FTO)/glass substrates were irradiated to demonstrate the applicability of obtained IPIB for irradiation of thin coatings without their deterioration. Single shot of IPIB with current density of 20 A/cm2 transformed Au film to spherical micro-particles, while after irradiation at the same fluence with 5 pulses of IPIB with current density of 4 A/cm2 Au coating was preserved as a film.

Efficient ion acceleration driven by a Laguerre–Gaussian laser in near-critical-density plasma

Laser-driven ion accelerators have the advantages of compact size, high density, and short bunch duration over conventional accelerators. Nevertheless, it is still challenging to generate ion beams with quasi-monoenergetic peak and low divergence in experiments with the current ultrahigh intensity laser and thin target technologies. Here we propose a scheme that a Laguerre–Gaussian laser irradiates a near-critical-density (NCD) plasma to generate a quasi-monoenergetic and low-divergence proton beam. The Laguerre–Gaussian laser pulse in an NCD plasma excites a moving longitudinal electrostatic field with a large amplitude, and it maintains the inward bowl-shape for dozens of laser durations. This special distribution of the longitudinal electrostatic field can simultaneously accelerate and converge the protons. Our particle-in-cell (PIC) simulation shows that the efficient proton acceleration can be realized with the Laguerre–Gaussian laser intensity ranging from 3.9 × 1021 W⋅cm−2–1.6 × 1022 W⋅cm−2 available in the near future, e.g., a quasi-monoenergetic proton beam with peak energy ∼ 115 MeV and divergence angles less than 5° can be generated by a 5.3 × 1021 W⋅cm−2 pulse. This work could provide a reference for the high-quality ion beam generation with PWclass laser systems available recently.

An ion beam system for calibration of space low-energy ion detectors

Abstract Low-energy ion detection in space is one of the most important interests of space exploration. An accurate calibration of this type of instrument is necessary to ensure the effectiveness and scientificness of the obtained data. And the ion source is the most critical equipment in a calibration facility. In this study, an ion beam system based on Kaufman ion source is designed, which can meet the ground calibration of space low-energy ion detection instrument in the low-energy range of 100–1,000 eV. The experimental research shows that when the beam intensity of the ion source is about 100 mA, the Faraday Cup collects about 1 mA of current, and the generated ion beam fluctuates less than 5% within 60 min, which can meet the ground calibration requirements of space low-energy ion detection instruments.

Effects of the temperature of a protic ionic liquid on ion beam production by vacuum electrospray

Ionic liquid ion sources generate ion beams from ionic liquids by vacuum electrospray. Electrospray characteristics generally depend on the physical properties of the liquids used. A key factor affecting physical properties is temperature. In this study, ion beam production was investigated using a protic ionic liquid, propylammonium nitrate (PAN), at temperatures ranging from 22 to 60 °C. An ion beam was produced using a needle emitter equipped with a cartridge heater, thermocouple, and sharpened glass rod externally wetted with PAN. The experimental results showed that the heating of the emitter increased the ion beam current. This will be due to an increase in the conductivity and a decrease in the viscosity of PAN with increasing temperature. Furthermore, the abundance of larger cluster ions increased, whereas that of smaller cluster ions decreased with increasing temperature. It turned out, however, that higher heating of the emitter stopped ion beam production. Two hypotheses for the beam stop are proposed and discussed.

Commissioning Results of the New Compact ECR Ion Source for Electrostatic Storage Ring at KACST

A compact microwave ECR ion source with low operating power was tested and commissioned for the ion injector line in the multipurpose low-energy ELASR storage ring facility at King Abdulaziz City for Science and Technology (KACST) in Riyadh. The compact ECR ion source can deliver singly charged ions with an energy of up to 50 keV and a beam current of up to 50 μA or up to 500 µA with a larger extraction aperture. The plasma in the ECR chamber is driven by a simple transmitter antenna, making the overall size of the ion source only 6 cm in diameter, which is relatively small when compared with other ECR systems. Additionally, the source operates without a high-voltage platform, which significantly reduces the overall footprint and simplifies the system operation. In this paper, the mechanical design and modeling of the ECR ion source are introduced, and the layout of the first part of the beam line is presented along with the numerical simulation results. In addition, the experimental results obtained for the first generated ion beam and commissioning of the ECR ion source are introduced and discussed.

Modeling of ion accelerated by borehole radiation pressure based on deep learning

Laser-driven ion acceleration has potential applications in high energy density matter, ion beam-driven fast ignition, beam target neutron source, warm dense matter heating, etc. Ultrashort relativistic laser interacting with solid target can generate ion beam with several hundreds of MeV in energy, and the quality of the ion beam depends strongly on the interaction parameters between the laser and the target. Development in deep learning can provide new method of analyzing the relationship between parameters in physics system, which can significantly reduce the computational and experimental cost. In this paper, a continuous mapping model of ion peak and cutoff energy is developed based on a fully connected neural network (FCNN). In the model, the dataset is composed of nearly 400 sets of particle simulations of laser-driven solid targets, and the input parameters are laser intensity, target density, target thickness, and ion mass. The model uses sparse parameter values to obtain the analysis results in a large range of parameters, which greatly reduces the computational amount of multi-dimensional parameters sweeping in a wide range. Based on the results of this model mapping, the correction formula for the ion peak energy is obtained. Furthermore, the ratio of ion cutoff energy to peak energy of each set of particle simulation is calculated. Repeating the same training process of ion peak energy and cutoff energy, the continuous mapping model of energy ratio is developed. According to the energy ratio model mapping results, the quantitative description of the relationship between ion cutoff energy and peak energy is realized, and the fitting formula for the cutoff energy of the hole-boring radiation pressure acceleration (HB-RPA) mechanism is obtained, which can provide an important reference for designing the laser-driven ion acceleration experiments.

Scientific programme at the Laser Laboratory for Acceleration and Applications

In recent years, laser-driven accelerators have emerged as a promising technology for the development of compact and cost-effective sources of high-energy particles and radiation. Here, we introduce our research programme at the Laser Laboratory for Acceleration and Applications, which focusses on high-power laser systems, development of high-repetition rate targetry, and biomedical applications of laser-based accelerators. Our recent results include the generation of high-energy proton and ion beams through laser-plasma acceleration, which have potential applications in materials activation for medical imaging. We have also investigated the feasibility of using laser-driven X-rays and ion beams for radiobiological research, including FLASH therapy and hadron therapy.

Characteristics of laminar ion beams accelerated via a few-joule laser pulse

Laser-driven carbon ion beams from a carbon foil target via a 2.5-J laser pulse are investigated with three-dimensional particle-in-cell simulations. An ion bunch with a narrow energy range exhibits a thin shell shape with a certain diameter. The ion cloud has a layered structure of these ion bunches with different energies. The divergences of the ion bunch in the laser inclination direction and perpendicular to it are different in an oblique incidence laser. In addition, theoretical formulas for the radius of the generated ion beam and the energy spectrum are derived, and they are shown to be in good agreement with the simulation results.

Study the Optimal Operative Conditions of New Glow Discharge Ion Source for Polymeric Treatment

The design, manufacturing, and systematic parametric evaluation of a modified glow discharge ion source (with a pear-shaped anode and a plane cathode) are detailed to extract low-power, high plasma density, and high-intensity ion beam current for material processing. The study includes determining the optimal operative conditions for ion source performance and optimizing its properties. The ion beam current was measured at various argon gas pressures and anode-cathode distances as well as its measurements at various ion source - collector plate distances. At the optimum settings, the influence of discharge pressure on the output current was evaluated using various gases (argon, oxygen, nitrogen and hydrogen). In addition, the influence of applied negative voltages on the extractor electrode (different hole diameters) on the generated ion beam current is being explored. Finally, SIMION computer program evaluated and studied ion beam optics. The simulation and experimental results for a highly efficient ion beam derived from the planned ion source agreed well.

Development of a new generation of ion beams

Ion beams have many applications. Junior Associate Professor Masahi Nojima, Research Institute of Science and Technology at the Tokyo University of Science, Japan, is working to create a new generation of ion beams. Already, he has successfully developed new techniques for producing focused ion beams (FIB). In his most recent work, Nojima has developed a metallic solution ion source that will be used to construct unknown functional materials by using ion beams made up of specific elements. The metallic solution ion source can generate a copy of an original structure using elementally selected materials. With support from the Japan Society for the Promotion of Science (JSPS), KAKENHI, the academic incentive system of the KIOXIA Corporation 2021 and the Toshiba Electric Devices & Storage Corporation 2021, Nojima is seeking to open up new materials for use as ion sources utilising electrospray ionisation (ESI) methods. By harnessing the elements of FIBs primarily created from liquid metal ion source (LMIS) by field ionisation processes, Nojima hopes to create new generations of ion beams. To date, he and the team have displayed the result of mass separating metallic ion solution ion beams on random conditions and, looking ahead, intend to estimate the stopping range of mass selected ion beams in solid materials.

Development of a new generation of ion beams

Ion beams have many applications. Junior Associate Professor Masahi Nojima, Research Institute of Science and Technology at the Tokyo University of Science, Japan, is working to create a new generation of ion beams. Already, he has successfully developed new techniques for producing focused ion beams (FIB). In his most recent work, Nojima has developed a metallic solution ion source that will be used to construct unknown functional materials by using ion beams made up of specific elements. The metallic solution ion source can generate a copy of an original structure using elementally selected materials. With support from the Japan Society for the Promotion of Science (JSPS), KAKENHI, the academic incentive system of the KIOXIA Corporation 2021 and the Toshiba Electric Devices & Storage Corporation 2021, Nojima is seeking to open up new materials for use as ion sources utilising electrospray ionisation (ESI) methods. By harnessing the elements of FIBs primarily created from liquid metal ion source (LMIS) by field ionisation processes, Nojima hopes to create new generations of ion beams. To date, he and the team have displayed the result of mass separating metallic ion solution ion beams on random conditions and, looking ahead, intend to estimate the stopping range of mass selected ion beams in solid materials.

Laser ion source for semiconductor applications

Carbon implantation can be effectively used for axial minority charge carriers’ lifetime control in various silicon bulk and epitaxial planar structures. When carbon is implanted, more stable recombination centres are formed and silicon is not doped with additional impurities, as for example, when irradiated with protons or helium ions. Economically, such a process competes with alternative methods, and is more efficient for obtaining small lifetimes (several nanoseconds). I-3 ion injector with laser-plasma ion source at Institute for theoretical and experimental physics (ITEP) is used as ion implanter in semiconductors. The ion source uses pulsed CO2 laser setup with radiation-flux density of 1011 W/cm2 at target surface. The ion source produces beams of various ions from solid targets. The generated ion beam is accelerated in the two gap RF resonator at voltage of up to 2 MV per gap. Resulting beam energy is up to 4 MV per charge. Parameters of carbon ion beam generated and used for semiconductor samples irradiation during experiments for axial minority charge carriers lifetime control in various silicon bulk and epitaxial planar structures are presented.

Generation of proton and carbon ion beam from laser ion source using hydrocarbon oil target

The supply of high-flux proton and carbon ions are required for applications such as accelerator-driven neutron sources and heavy ion radiotherapy. So far, it is shown that a laser ion sources using the target of plastics made of hydrocarbons can provide protons and carbon ions. On the other hand, due to the damage of the target by laser irradiation, it is necessary to change the laser irradiation position every time, and the number of ion supply is limited to the area of the laser target. To solve the problem of target damage, we suggest a laser target in which the surface is continuously renewed by flowing hydrocarbon oil instead of solid hydrocarbon. In this study, we demonstrated the generation of protons and carbon ions using the target made of a hydrocarbon oil for a diffusion pump.

Study of the propagation of an intense ion beam to the target

The results of studying the intense ion beam propagation with peak energy up to 330 keV are presented. The ion beam was injected into the metal tube made from stainless steel in the form of a hollow cone. It was found that the ion beam focused due to neutralizing the space charge and reducing the divergence of ions. Neutralization of the beam space charge was investigated by measuring its electric potential. The average energy density of a beam increased up to 2.9 J/cm2 over the beam cross-section in the focal plane. The ion beam current density in the tube rose by a factor of 3 in comparison with geometric focusing. The analysis of the surface structure of the ion beam spot obtained on the stainless steel AISI 304 plate was done.

Generation of high-power submillisecond metal ion beams

The possibility of using one grid electrode in the form of a part of a sphere for extraction from a free plasma boundary and focusing of metal ions is shown for the first time using titanium ions as an example to form a pulsed beam with a duration of 500 μs and a power density reaching 105 W/cm2. The results of studying the influence of the amplitude of the accelerating voltage in the range of 9-30 kV and the size of the grid cells on the efficiency of space charge neutralization and ion beam focusing are presented. Keywords: metal ions, vacuum arc plasma, submillisecond beams, high power density.

Copper ion beam emission in solid electrolyte Rb4Cu16I6.5Cl13.5

Copper ion conducting solid electrolyte Rb4Cu16I6.5Cl13.5 was prepared by means of mechano-chemical method. The structure and morphology of the powder was investigated by x-ray diffraction and scanning electron microscopy. The grain size was estimated to be 0.2–0.9 μm and the ionic conductivity at room temperature was approximately 0.206 S/cm. The solid electrolyte Rb4Cu16I6.5Cl13.5 was exploited for copper ion beam generation. The copper ion emission current of several nA was successfully obtained at acceleration voltages of 15 kV and temperature of 197 °C in vacuum of 2.1 × 10−4 Pa. A good linear correlation between the logarithmic ion current (log I) and the square root of the acceleration voltage (U acc) at high voltage range was obtained, suggesting the Schottky emission mechanism in the process of copper ion beam generation.

The influence of gas purification and addition of macro amounts of metal-carbonyl complexes on the formation of single-atom metal-carbonyl-complexes

Abstract Using the Fast On-line Reaction Apparatus (FORA), the influence of various gas-purification columns onto the formation of metal carbonyl complexes (MCCs) under single-atom chemistry conditions was investigated. MCCs were synthesized from single atoms of Mo, Tc, Ru and Rh being produced by the spontaneous fission of 252Cf and recoiling into a CO-gas containing carrier gas atmosphere. The in-situ synthesized MCCs were volatile enough to be transported by the carrier gas to a charcoal trap where they were adsorbed and their subsequent decay was registered by γ-spectrometry. It was found that the type and combination of purification columns used to clean the applied CO-gas strongly influences the obtained formation and transport yields for all MCCs. With the exception of Rh-carbonyl, intense gas-purification strategies resulted in reduced formation and transport yields for MCCs in comparison with less efficient or even completely missing purification setups. It was postulated that the observed reduction in yield might depend on the content of Fe(CO)5 and Ni(CO)4, as well as potentially other MCCs, in the CO-gas, being formed by the interaction between CO and the steel-surfaces of FORA as well as from impurities in the used charcoal traps. Subsequently, it was shown that macro amounts of Fe(CO)5, Ni(CO)4, Mo(CO)6 and Re2(CO)10 added to the used process gas indeed increase significantly the overall yields for MCCs produced by 252Cf fission products. Ni(CO)4 appeared the most potent to increase the yield. Therefore, it was used in more detailed investigations. Using isothermal chromatography, it was shown that Ni(CO)4 does not affect the speciation of carbonyl species produced by the 252Cf fission product 104Mo. For 107Tc, 110Ru and 111Rh a speciation change cannot be excluded. For 111Rh a speciation change cannot be excluded. An inter-carbonyl transfer mechanism is suggested boosting the formation of MCCs. The current discovery might allow for new opportunities in various research fields, which are currently restricted by the low overall yields for MCCs produced under single-atom chemistry conditions. Examples are the chemical investigation of transactinides or the generation of radioactive ion beams from refractory metals at accelerators.

Generation and stopping of laser-driven two-component ion beam

The generation and stopping of a laser-driven two-component ion beam are investigated by three-dimensional particle-in-cell simulation and an extended stopping model. It is found that a two-component ion beam with the tunable composition ratio can be obtained from the two-species-ions sandwich target interacting with a relativistic laser pulse. When the generated proton beam mixed with a certain portion of carbon ions is transporting in fully ionized dense plasma, the beam stopping power is significantly enhanced compared to a pure proton beam. The maximum penetration depth is sharply reduced, and the Bragg peak with a higher magnitude appears earlier at the end of their paths, which is beneficial for achieving more localized energy deposition. The effect of heavy ion mixing on proton beam driven fast ignition is also discussed. A simple theoretical model is established, indicating that the required ignition time is relatively delayed for a heavy-ion doping case. For a small hot-spot size, it is possible to achieve the fusion ignition for a low mixed ratio. However, it is difficult to maintain a high fuel temperature due to the growing energy loss originating from mechanical work and thermal conduction.