A new tandem type source on the basis of electron cyclotron resonance (ECR) plasma has been constructing for producing synthesized ion beams in Osaka Univ. [1] Magnetic mirror field configuration with octupole magnets can be controlled to various shape of ECR zones, namely in the second stage plasma to be available by a pair mirror and a supplemental coil. Noteworthy correlations between these...
A high flux, low energy ion beam facility has been designed, developed and commissioned at the Inter University Accelerator Centre (IUAC), New Delhi. [1, 2]. It mainly consists of a 2.45 GHz microwave ion source, a compact multi-electrode extraction system and an experimental chamber for performing experiments using intense ion beams in the energy range of a few keV to a few tens of keV....
Currently, the 28 GHz electron cyclotron resonance ion source (ECRIS) has been developed to produce a high current heavy ion at korea basic science institute (KBSI). The high voltage platform of 28 GHz ECRIS is essential to deliver an ion beam to the next acceleration stage. In order to ensure the electrical safety, the high voltage platform has been designed considering dielectric...
Electron cyclotron resonance ion sources (ECRIS) have been essential in the research and applications of nuclear physics over the past 40 years. They are extensively used in a wide range of large-scale accelerator facilities for the production of highly charged heavy ion beams of stable and radioactive elements. Plasmas of electron cyclotron resonance ion sources (ECRISs) are prone to kinetic...
It is very likely that a long lifetime of cesiation in SNS RF surface plasma sources (SPS) can be connected with deposition into the emitter/converter cone and to the discharge chamber some specific carbon films.
The work function dependence for graphite with alkali deposition has no minimum typical for metals and semiconductors and a final work function is higher. By this reason the...
Design of the high-current ion injector for ions with $z/A≥1/3$ is described. The system consists of a laser-plasma generator based on a repetition rate CO$_2$ laser, a vacuum target chamber with optical focusing system, a beam extraction and transport system, and RFQ accelerator with $z/A≥1/3$. The goal of the work is to optimize parameters of all of the above components for maximum ion beam...
Electron Beam Ion Source (EBIS) has been one of the widely used table-top devices for the production of highly charged ions due to its high purity of charge states. At Korea Multipurpose Accelerator Complex (KOMAC), we have constructed a compact EBIS test bench, consisting of a EBIS-A (advanced EBIS from Dreebit GmbH, Germany), a Wien filter and a Faraday cup. The Wien filter with a permanent...
IsoDAR is an experiment under development to search for sterile neutrinos using the isotope Decay-At-Rest (DAR) production mechanism, where protons impinging on $^9$Be create neutrons which capture on $^7$Li which then beta-decays producing $\bar{\nu}_e$. As this will be an isotropic source of $\bar{\nu}_e$, the primary driver current must be large (10 mA cw) for IsoDAR to have sufficient...
Compact H$^{+}$ ECR Ion Source using permanent magnets is under development. A pulsed gas injection system, achieved by a fast piezo gas valve, can reduce the gas load to a vacuum evacuation system. This feature is suitable when the ion source is closely located to an RFQ. Use of permanent magnets reduces the size. Achieved performance will be presented.
A direct comparison of Balmer line emission from J-PARC RF ion source (RFIS) plasma has been made between photometry measurement and 3D3V numerical analysis.The J-PARC RFIS has internal antenna coil for injection of a few 10 kW RF power with RF frequency of 2 MHz. Negative hydrogen ion ($\text{H}^-$) current of 45 mA is extracted with energy of 50 keV during the user operation in present. In...
MARS (Mixed Axial and Radial field System) is a new superconducting magnet underdevelopment with a novel coil layout for more efficiently generating high strength minimum-B fields for the next generation of Electron Cyclotron Resonance (ECR) ion source. It consists of a hexagonal closed-loop-coil and a set of auxiliary solenoids. A new quench protection system is needed for a MARS magnet to be...
Contemporary negative hydrogen (H$^-$) ion sources are operated with Cs ovens, and some part of the H$^-$ ion current extracted from the source is believed produced at the surface of the biased plasma electrode. The principle mechanism of the H$^-$ ion current production can be due to the reflection of atomic hydrogen, but this hypothesis has not been directly confirmed in the actual ion...
To improve the directivity of source plasma ions supplied to the extraction gap of a laser-ablation ion source (LAIS), the behavior of a laser-produced dense plasma flow modulated by a divergent magnetic field was investigated in detail. A magnetic field having a "nozzle-like" structure was induced by a pulsed solenoid near the laser target in synchronization with laser irradiation. The...
Fundamental data on surface reflection and adsorption/implantation are necessary for understanding edge plasma physics to design future fusion reactor components. A large divergent angle arising from low energy ion beam transport reduces signal intensity to make study on fundamental processes more difficult. A 40 mm diameter, 70 mm long compact ion source is being developed aiming at...
The multi-beam acceleration method is an acceleration technique for low-energy high-intensity heavy ion beams, which involves accelerating multiple beams to decrease space charge effects, and then integrating these beams by a beam funneling system. At the Tokyo Institute of Technology, in order to demonstrate that a four-beam Interdigital-H type Radio Frequency Quadruple (IH-RFQ) linear...
A compact accelerator for high energy carbon-ion radiotherapy (C-ion RT) has been studied in Heavy Ion Medical Accelerator in Chiba (HIMAC) at National Institute of Radiological Sciences (NIRS) since 2004. Compact accelerator for Gunma University (Gunma University heavy ion medical center: GHMC), Saga C-ion RT facility (Saga Heavy Ion Medical Accelerator in Tosu: SAGA HIMAT) and Kanagawa C-ion...
The version 2 and 3 of the 18 GHz PHOENIX ECR ion source have been developed in the framework of the SPIRAL2 project. The former V2 design focused on maximizing the radial magnetic confinement at the plasma chamber wall, resulting in a compact chamber volume of 0.6 liter with a diameter of 62 mm. The new V3 design focused on a larger diameter of 89 mm (chamber volume 1.4 liter) keeping the...
Charged muons as Muonium negative ions (consisting of positive Mu ¬ meson and 2 electrons) have affinity S=0.75 eV. Muonium have ionization energy I=13.6 eV. Muonium negative ions were observed in 1987 [1], [2] by interaction of muons with a foil. In this work an efficiency of transformation of Mu mesons to negative muonium ions were very low 10-4. However, with using tungsten or palladium...
A quartz-chamber 2.45 GHz ECR ion source was designed for diagnostic purpose at Peking University [Patent Number: ZL 201110026605.4]. It can produce a maximum of 84 mA hydrogen ion beam working at pulsed mode and the root-mean-square (RMS) emittance of this proton beam is smaller than 0.2 π∙mm∙mrad. In our primary work, electron temperature and electron density inside the plasma chamber have...
It has been investigated how to produce various ions efficiently on the electron cyclotron resonance ion source (ECRIS) in Osaka Univ. We attach the movable reflector, like bias plate, called plate-tuner, which is inserted from the mirror end plate opposite side to the extractor in the ECRIS. Standing waves are generated by placing the plate-tuner at nodes of the microwave and the microwave...
The installation of molybdenum liners in the ion source NIO1 (Negative Ion Optimization phase 1) has proven to be successful in order to largely decrease the contamination of rf window by wall sputtering; intense hydrogen plasma are thus achievable even at moderate rf power (1200 W) in a continuous regime operation (much longer than one hour), which enabled prolongated campaign at several...
The paper presents the results of experimental studies of the production of high intensity low ion energy repetitively pulsed beams of aluminum. The generation of metal plasma was conducted by a DC vacuum arc evaporator. The formation of ion beams was carried out using an original developed system combining plasma–immersion approach for extraction and acceleration of ions and their further...
For the FAIR anti-proton research the compact proton linac will produce proton beams with energy of 70 MeV that will be injected into upgraded Heavy Ion Synchrotron (SIS 18), accelerated to 4 GeV, and further accelerated to 30 GeV in SIS 100. The commissioning of the proton injector which would serve for the injection into the proton linac is already started at CEA/Saclay. The ion source...
We are presenting the simulation results of the hot tungsten filament behavior in a Freeman ions source installed in the LANL electro-magnetic isotope separator (EMIS). The Freeman source enables us to ionize and extract high intensity single-charge ion beams from different gases as well as from various solid materials in order to purify the content of a selected isotope [1].
We have modified...
The upcoming FAIR facility (Facility for Antiproton and Ion Research) will provide wide opportunities for investigation and research programs in different branches of science including antiproton physics, bio and material research, nuclear astrophysics and many others. A significant part of these programs require high intensity primary beams of heavy ions: $^{197}$Au, $^{208}$Pb, $^{209}$Bi...
At KVI-CART, an upgrade of the AECR ion source is in preparation, with the main objective to increase the intensity, stability and purity of the highly charged ion beams. To increase the intensity a new hexapole will be installed with stronger Nd-Fe-B magnets. To further increase the magnetization, the temperature of the hexapole bars will be lowered, making use of the temperature dependence...
The volumetric Kα emission rate emitted from the Electron Cyclotron Resonance (ECR) heated plasma of an ECR ion source (ECRIS) can be used to estimate the inner shell ionization rate of a gas species. Additionally, the thick target radiation originating from the walls of the plasma chamber can be used to estimate the energetic electron losses from the magnetic confinement system of the ECRIS....
We have tried to reveal a mechanism of laser ablation plasma generation through the developing Laser Ion Source (LIS) and confirmed that charge state distribution is forcefully affected by the laser target thickness. A LIS generates pulsed highly charged ion beams by irradiating solid material targets with high intensity pulsed laser. In the past, we examined the effect of laser target...
The 400 kV ion implanter in TIARA facility [1] provides variety of low charge DC ion beams of C, Al, Ti, Cu, Au, Pt, etc. mainly for material sciences. Most of beams are produced from solid materials by a Freeman type ion source equipped with sample vaporization oven. In the case of high melting point materials, the beam current is insufficient (below a few microamps) and decreases with time....
We are studying possibility to use sub nanosecond lasers to deliver low charge state ion beams from various target materials. Since 2014, a laser ion source (LIS) is in operation to provide singly charged heavy ion beams to user facilities at Brookhaven National Laboratory. For the LIS, 1064 nm, 6 ns single resonator ND-YAG lasers are used. It is required to operate the LIS for more than half...
The paper presents the results of experimental studies of the formation of high-intensity low ion energy pulsed beams of gases, gases and metals.The generation of gas plasma was conducted by a source based on non-self-sustained arc discharge with the hot cathode. In the case of mixed ion beams of gas and metal, the plasma formation was carried out by the source with the hot cathode and vacuum...
RAON fully superconducting ECRIS which plasma chamber volume of 10 liters is adapted and uses a 28 GHz MW power as a main power source and an 18 GHz MW power as a secondary power source. We characterized our ion source at a relatively low magnetic field just with an 18 GHz MW power. A reference O$^{7+}$ beam was monitored with the experimental parameters such as MW power, vacuum pressure, and...
Novel device based on the technology of Main Magnetic Focus Ions Source [1] has been developed recently at JINR. The electron beam characterized by the current of 50 mA and the energy exceeding 30 keV is focused by the magnetic system consisting of the radial permanent magnets. Highly charged ions are produced in the main focus of magnetic lens, where the electron current density exceeds 10...
MEDeGUN [1] is an electron gun to be used in an Electron Beam Ion Source (EBIS) designed to serve as C$^{6+}$ injector for LINAC-based 2nd generation hadron therapy facilities [2]. The latter require short pulses of at least 8 x 10$^8$ particles with a repetition rate of 400 Hz, which exceeds the possibilities of currently used electron cyclotron resonance ion sources (ECRIS) and EBISes.
The...
Multiple frequency heating is one of the most effective techniques to improve the performances of ECR ion sources. It has been demonstrated that the appearance of the periodic ion beam current oscillations in ECRIS at high heating power and low magnetic field gradient is associated with kinetic plasma instabilities. Recently it was proven that one of the main features of multiple frequency...
Elevation of ion charge states in broad beam of vacuum arc source leads to proportional increasing of ion beam energy without elevation of accelerating voltage. The ion charge states were elevated by using of high current vacuum arc with a few microsecond pulse duration. The heavy ion (bismuth) beam of several microseconds with pulsed ion beam current of several hundreds of milliamperes and...
Pulsed and CW operation of negative ion radio frequency surface plasma source (RF SPS) with a solenoidal magnetic field and external solenoidal and saddle type antennas are described. Dependence's of a beam current and extracted current on RF power, extraction voltage, solenoid and filter magnetic field, gas flow are presented. Compact design of RF SPS is presented.
Acknowledgement
The...
The difference in negative ion source performance between hydrogen and deuterium is investigated for three types of negative ion source design: charge exchange, surface and volume sources. The early results obtained at Ecole Polytechnique (France) with volume sources operated with and without Cs are reviewed to compare the characteristics of the source charged with deuterium to those of the...
X-ray imaging and numerical simulations demonstrate that the RF power deposition in ECRIS plasmas is not concentrated in the near-axis region, as it would be desirable in order to maximize the ion beam brilliance. There are different arguments to explain this occurrence as due to the symmetry of the plasma chamber. In this "aperture coupled" cylindrical cavity resonator, in fact, any eigenmode...
Huazhong University of Science and Technology (HUST) is developing an RF based negative ion source. Numerical simulation of the 1 MHz RF driver has been performed using a commercial high frequency FEM software. Differing from conventional inductively coupled plasma (ICP) source simulations, which exclude the effect of Faraday Screen (FS) and simplify the multi-turn helix RF antennas as...
The FAIR facility will require low duty cycle intense heavy ion beams which cannot be produced by the CAPRICE Electron Cyclotron Resonance Ion Source (ECRIS) installed at GSI. In order to fulfill this requirement an upgrade of the high charge state injector is mandatory. An experimental investigation at the ECRIS testbench was carried out with the aim to enhance the extracted ion currents in...
After the development in the 90’s of the mono-charged ion source [1] based on a axisymmetric magnetic structure, the next step towards multicharged ion source has been undertaken with the Multigan ion source [2]. The preliminary results did not fully demonstrate the ability of this source to produce high charge states. Therefore, GANIL and Pantechnik got both involved in a collaboration to...
This paper reports on experiments to study the effects of sinusoidal microwave power Amplitude Modulation (AM) on the performance of Electron Cyclotron Resonance (ECR) ion sources. The study was motivated by an inherent property of high frequency power sources such as gyrotrons, which exhibit amplitude modulation of the microwave power due to the use of high frequency switching power supplies...
The p(7Li,n)7Be reaction can be used to produce forward neutron beam based on the principle of inverse kinematics, which is useful to reduce the background of the measurement of prompt fission γ-ray emission from fast neutron induced fission of $^{235}$U and 238U. A hybrid $\text{7Li3}^+$ ion source is going to be adopted to produce 10 eμA beam for this experiment. Previously a high B...
For the production of high intensity $^{11}$C beams for image-accompanied hadron therapy, we present our proposal for a radioactive ion beam production system based on the ISOL technique (Isotope Separation On-line), operated with a compact 1+ electron cyclotron resonance ion source (ECR). Carbon therapy is a very precise treatment for cancers with localized tumors. However, such treatments...
In this paper measurements on the production of high intensity, medium charge-state Nickel-ion beams with high isotopic purity using the Metal Ion from Volatile Compound (MIVOC) Method are presented. Commercially supplied Nickelocene (Ni(C5H5)2) with natural abundance, Nickelocene with 99% enriched 60-Nickel and 98% enriched 62-Nickel were investigated with a 14.5 GHz ECRIS4. Mass over charge...
For development of a cesium-free negative ion source, we have carried out the experimental observation and modeling of negative ion, atomic and molecular ions in hydrogen sheet plasma. The sheet plasma is suitable to produce negative ions, because the electron temperature in the central region of the plasma is as high as 10 -15 eV, whereas in the periphery of the plasma, a low temperature of a...
Laser ablation of a solid oxide compound material makes the ion production of gaseous elements possible. Using an aluminum and alumina for the target in the laser ion source, the plasma characteristics in a low laser energy scheme was investigated to understand the difference in ion production of oxygen from the aluminum oxide material. The Faraday cup measurements of the laser produced plasma...
Nowadays one of widespread types of ion sources is systems with plasma heating by microwave radiation in a magnetic field under conditions of the electron cyclotron resonance (ECR). In a purpose to obtain high values of ion beam currents there is a need of high plasma density. Due to this fact one of the main directions of ECR ion sources development is to increase the frequency and power of...
There has been considerable research in proton beam production with laser-produced plasma, due to its important applications in various fields, such as cancer therapy and neutron source for radiography. While the feasibility of a laser ion source as the pre-injector of cancer therapy facilities in terms of the capability of the carbon ion beam production has been demonstrated in our previous...
Compact ECR plasma device was built in the Atomki ECR Laboratory called ECR Table Plasma Generator (TPG). It consists of a large plasma chamber (ID=10 cm, L=40 cm) and of a thin NdFeB hexapole magnet with vacuum and gas dosing systems. For microwave coupling low power TWTA is applied, operating in the 6-18 GHz frequency range. There is no axial magnetic trapping and there is no ion extraction....
To further increase the beam intensity of highly charged U ion beam for RIKEN radio-isotope (RI) beam factory project and to produce the intense beam of medium mass heavy ions, such as Ti, V and Cr ions, for super-heavy element ($Z = 119$ and 120) search experiments, we tried to improve the performance of the RIKEN 28 GHz SC-ECRIS in last two years.
In the test experiment, we successfully...
A positive ion source with RF discharge in solenoidal magnetic field is described. In this paper we present an overview of the positive ions production in saddle antenna (helicon discharge) radio frequency (SA RF) ion sources. An efficiency of H+ ion production in recently developed RF sources with solenoidal antennas was improved to 1.5-2 mA/kW. About 60 kW of RF power is typically needed...
Argon plasma behavior in a 2.45 GHz electron cyclotron resonance (ECR) plasma reactor is studied by means of a finite element software “COMSOL”. Using a multi-physics approach, we have simulated the magnetic field distribution, the microwave power deposition and the plasma properties such as potential, density, temperature etc. We report some results on investigation of the effects of various...
The vacuum arc discharge with a deuterium impregnated metal cathode is a popular source of deuterium ions, which is widely used in neutron generators [1-3]. Recently, metal deuteride film cathode for vacuum arc discharge is studied by Efim M. Oks [1,4]. This paper reports on a study of the properties of the plasma and gas produced in a vacuum arc discharge with Scandium deuteride thin film...
Since 2012, the INFN ion source group has been undertaking an intense activity on numerical modelling, started in a European context with the EMILIE Project, and presently continuing in the framework of the PANDORA project. The work mainly concerns the study of two aspects: on one hand, the interaction of an ion beam with a magnetized plasma, a topic of interest in the field of ECR-based...
A new type of ECR ion sources – a gasdynamic ECR ion source was invented recently at the Institute of Applied Physics (IAP RAS, Nizhniy Novgorod, Russia). The main advantages of such devices are extremely high ion beam current with a current density up to 600 – 700 $mA/cm^2$ in combination with low emittance i.e. normalized RMS emittance below 0.1 π•mm•mrad. The main part of previous...
The Accelerator Laboratory at the University of Jyväskylä (JYFL) has performed radiation effects testing of electronics since 1998 using a K130 cyclotron and cocktail beams produced with ECR ion sources (ECRIS). Currently most of the tests are done at 9.3 MeV/u energy which is achievable with the charge states produced by the 14 GHz ECRIS of the laboratory. The radiation effects community has...
Tandem type hydrogen negative ion (H$^-$) sources are generally designed to have two plasma regions of different average electron energies. The higher and lower electron energy regions are called “driver region” and “extraction region”, respectively [1]. The driver region should contain electrons with energy high enough to produce excited hydrogen molecules for H$^-$ production. On the other...
Recent investigations of pulsed gasdynamic ECR plasma [1] resulted in development of a new type of electron cyclotron resonance ion source (ECRIS) – a so-called gasdynamic ECRIS - at the Institute of Applied Physics (IAP RAS). The main advantages of gasdynamic ECRIS are extremely high ion beam current in comparison with conventional classical ECRIS - current density up to 600 – 700...
The GTS-LHC ECR ion source at CERN provides heavy ion beams for the chain of the accelerators from Linac3 up to the LHC. For the lead runs the solid material is evaporated in internal ovens. The processes within these ovens are not well understood and experiences during the operation suggest there is room for improvement regarding the beam stability and the time between necessary refills.
A...
Heating the plasma of an Electron Cyclotron Resonance Ion Source (ECRIS) simultaneously with two microwave power sources operating at different frequencies has been proven to enhance the high charge state production in comparison to conventional single frequency heating. Despite the success of this technique, the underlying physics remains not well understood. A commonly applied scheme used...
Superconducting ECR ion source incorporated with the cutting edge techniques provides the ultimate conditions for highly charged ion beam production. In the last 12 years (since ICIS 2005 in Caen, France), ECR ion source performance has got remarkable improvement, most of the typical ion beam intensity records have been renewed almost every year, with the great efforts in superconducting ECR...
The 28 GHz superconducting electron cyclotron resonance (ECR) ion source has been developed to produce a high current heavy ion beam for the linear accelerator at KBSI (Korea Basic Science Institute). In the last year, an ECR ion source was upgraded to improve performance. The extraction system was changed to prevent arcs which were generated between the negative electrode and ground...
The intensity of the ion beam extracted from an electron cyclotron resonance ion source (ECRIS) depends on the production rate of ions and the efficiency of the ion beam formation and transport. The production of Ar$^{9+}$ ions in an ECRIS plasma and the beam formation of the resulting Ar$^{9+}$ ion beam have been studied with the JYFL $14~\mathrm{GHz}$ ECRIS by using optical emission...
Earlier studies [1] on the frequency tuning effect in the 10 GHz NANOGAN ECR ion source have shown that larger intensities of medium and highly charged ions were extracted as compared to the source operation at 10 GHz and that the beam quality obtained was even better. In the present study we have tried to systematically correlate the x-ray intensities of the warm electrons measured at the...
The dual hollow cathode ion source for metal ion beams (Duhocamis) was introduced in 2007. The Duhocamis is derived from the indirectly-heated cathode GSI-PIG ion source and more suitable for producing various metal ion beams. To understand the discharge characteristics of Duhocamis, a series of arc discharge experiments have been performed on the test bench at Peking University. The transfer...
ECR ion source is considered to be the most efficient facility for generating highly charged ions beams, because of its board ion variety, high charge-state and beam stability, repeat-ability, etc. Compared with the intensive experiments, the study on theories and simulations of ECR ion source is more rare and immature due to its complicated physical phenomena and the huge computational cost....
Electromagnetic isotope separator is the important machine for isotope enriching of which ion source is the critical part. In China, the only one yielding-type electromagnetic isotope separator, named EMIS-170, locates in China Institute of Atomic Energy. It has been playing important role in providing highly enriched stable isotopes for many applications domestically, and the ion source used...
The high-energy ion nanoprobe LIPSION* of the Universität Leipzig consists of a 3 MV singletron accelerator in combination with an ion nanoprobe which presently focusses protons and helium ions to diameters in the sub-100 nm range.
The currently used RF ion source in the accelerator dominantly produces single-charged ions of a mass range of hydrogen up to xenon. Their ionic charge state 1 (at...
Super-heavy-element factory is under development at the Flerov Laboratory for Nuclear Reactions, JINR, Dubna. The factory will include DC-280 cyclotron, which will be equipped with two 100 kV high voltage platforms. A high charge state all-permanent magnet 14 GHz ECRIS – DECRIS-PM has been designed and fabricated to provide intense multiple charge state ion beams. The request for the source is...
Models for surface interactions and emission in ion sources may be based on surface measurements taken with quite different nearby field strengths, particle spectra, charge densities, and connected to power supplies with different VI characteristics, or even different material composition to those in the device being simulated. Particularly, standard models available in many codes do not take...
The extraction of negative ions from a plasma is necessarily accompanied by electrons, which are controlled with a transverse magnetic field. A full numerical analysis of the 3D model is hindered by the computational load and by the rapidly growing electric field towards extraction, so that we pass from quasi-neutral plasma with collisional transport to collision-less sheath to beam region.
It...
The GTS (Grenoble Test Source) electron cyclotron resonance ion source, operated at 14.5 GHz, provides multiply charged heavy ion beams for the ARIBE (Accélérateurs pour les Recherches Interdisciplinaires avec les Ions de Basse Energie) facility at GANIL (Grand Accélérateur National d’Ions Lourds). In order to increase the beam currents and charge states available for experiments and to have a...
The CAPRICE-type ECR ion source mVINIS has been upgraded by increasing its magnetic field to improve a plasma confinement and thereby enhance the source performance. This modification made it also possible to increase the internal diameter of the plasma chamber and to replace the coaxial microwave input on the waveguide. Some major subsystems such as: the vacuum system, the microwave system,...
Neutron tomography is one of the most exciting recent achievements of nuclear physics. It opens up opportunities for a wide range of various microscopic studies of physical, chemical and biological objects. It is of note that neutron tomography requires dedicated neutron sources, i.e. paraxial sources with low angle spread. The only sources now able to deliver required neutron beams with...
