Thick Target Research Articles

High order modes of intense second harmonic light produced from a plasma aperture

Because of their ability to sustain extremely high-amplitude electromagnetic fields and transient density and field profiles, plasma optical components are being developed to amplify, compress, and condition high-power laser pulses. We recently demonstrated the potential to use a relativistic plasma aperture—produced during the interaction of a high-power laser pulse with an ultrathin foil target—to tailor the spatiotemporal properties of the intense fundamental and second-harmonic light generated [Duff et al., Sci. Rep. 10, 105 (2020)]. Herein, we explore numerically the interaction of an intense laser pulse with a preformed aperture target to generate second-harmonic laser light with higher-order spatial modes. The maximum generation efficiency is found for an aperture diameter close to the full width at half maximum of the laser focus and for a micrometer-scale target thickness. The spatial mode generated is shown to depend strongly on the polarization of the drive laser pulse, which enables changing between a linearly polarized TEM01 mode and a circularly polarized Laguerre–Gaussian LG01 mode. This demonstrates the use of a plasma aperture to generate intense higher-frequency light with selectable spatial mode structure.

Quantitative assessment of radionuclide production yields in in-beam and offline PET measurements at different proton irradiation facilities

Objective. Reliable radionuclide production yield data are a prerequisite for positron-emission-tomography (PET) based in vivo proton treatment verification. In this context, activation data acquired at two different treatment facilities with different imaging systems were analyzed to provide experimentally determined radionuclide yields in thick targets and were compared with each other to investigate the impact of the respective imaging technique. Approach. Homogeneous thick targets (PMMA, gelatine, and graphite) were irradiated with mono-energetic proton pencil-beams at two distinct energies. Material activation was measured (i) in-beam during and after beam delivery with a double-head prototype PET camera and (ii) offline shortly after beam delivery with a commercial full-ring PET/CT scanner. Integral as well as depth-resolved β +-emitter yields were determined for the dominant positron-emitting radionuclides 11C, 15O, 13N and (in-beam only) 10C. In-beam data were used to investigate the qualitative impact of different monitoring time schemes on activity depth profiles and their quantitative impact on count rates and total activity. Main results. Production yields measured with the in-beam camera were comparable to or higher compared to respective offline results. Depth profiles of radionuclide-specific yields obtained from the double-head camera showed qualitative differences to data acquired with the full-ring camera with a more convex profile shape. Considerable impact of the imaging timing scheme on the activity profile was observed for gelatine only with a range variation of up to 3.5 mm. Evaluation of the coincidence rate and the total number of observed events in the considered workflows confirmed a strongly decreasing rate in targets with a large oxygen fraction. Significance. The observed quantitative and qualitative differences between the datasets underline the importance of a thorough system commissioning. Due to the lack of reliable cross-section data, in-house phantom measurements are still considered a gold standard for careful characterization of the system response and to ensure a reliable beam range verification.

Bio-based adhesive derived from citric acid and sorbitol for wood-composite manufacture

ABSTRACT Wood composites are manufactured by joining wood fibres, strands, or particles together with an adhesive, but it is necessary for eliminate the use of formaldehyde-based adhesives in the manufacture of wood composites for the sake of indoor air quality and human health. This initial study has demonstrated the use of sorbitol and citric acid as a potential bio-based formaldehyde-free adhesive for wood-composite manufacture. A solution of citric acid and sorbitol in water was sprayed onto wood particles which were then pressed at 160°C, 180°C, or 200°C for 13 min, to produce boards with a target thickness of 8 mm. The FTIR spectra contained an absorption band at 1720cm−1, presumably due to the esters of citric acid and sorbitol. Pressing of a temperature of 200°C gave boards with the highest modulus of elasticity and the highest internal bond strength. The results reveal a new potential bio-adhesive for the manufacture of wood composites.

Development of a Sealed Li target as an accelerator-driven neutron source for Boron neutron capture therapy at Nagoya University

Nagoya University is developing a Sealed lithium (Li) target based on a new concept for an accelerator-driven neutron source for Boron neutron capture therapy. The Sealed Li target is a thick Li target with the new concept of sealing Li with Ti foil and stopping protons within Li. The incident proton beam on the target is generated by the Proton-dynamitron (IBA) accelerator and has a maximum energy of 2.8 MeV and a current of 15 mA (heat input of 6.6 MW/m2). In this paper, a test sample made with a small amount of Li was prepared to evaluate the performance of the Sealed Li target. We called the test target. When irradiated with a heat input of 4.6 MW/m2, the Ti foil on the surface of the test target was not damaged, although some Li melted and a dent with the same shape as the beam diameter was formed. Furthermore, the heat removal performance of the test target was evaluated using simulation software and the finite element method. The maximum temperature of the target surface was 144.4 °C when a heat input of 5.0 MW/m2 was calculated. Assuming that the bondability between Ti foil and Li is poor, the calculation was carried out by simulating the presence of cavities at the Ti foil–Li​ interface. As a result, we suggested that the presence of than 2 mm diameter cavity at the interface between Ti foil and Li would melt the Ti foil and damage the target. In order to obtain the ideal result, it was necessary to further improve the adhesion between Ti foil and Li, but we were able to confirm the performance of the sealed Li target with a new concept.

Plasma and Light Flash Radiant Features Generated by Al/PTFE Projectile High-Velocity Impact Thin Aluminum Target

To reveal the characteristic parameters and the evolutionary rules of plasma and light flash radiation produced by aluminum powder/polytetrafluoroethylene (Al/PTFE) projectile hypervelocity impacting on 2A12 thin aluminum plate, the Al/PTFE projectile was obtained by the improved sintering process of the sample, which is based on the process of the traditional Al/PTFE (mass percentage ratio of aluminum powder and PTFE is 26.5%/73.5%). The dynamic compressive strength of the sample was characterized by the self-constructed split Hopkinson pressure bar (SHPB) system. Meanwhile, the experiments, enhanced Al/PTFE projectile (mass 0.22 g, size <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$5\times5$ </tex-math></inline-formula> mm) impacting on 2A12 aluminum targets with the thicknesses of 2 and 3 mm at different impact speeds (1.95–2.45 km/s), have been performed using a two-stage light gas gun loading system combining with a high-speed camera acquisition system, a transient fiber pyrometer measurement system, and a plasma characteristic parameter diagnostic system. The electron temperature, electron density of plasma, and the radiant temperature (in the range of visible light wavelength) of light flash have been experimentally studied. The results show that the dynamic compressive strength of the Al/PTFE specimen with rapid cooling was significantly improved at the strain rate of 4000 s <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−1</sup> comparing with the traditional Al/PTFE projectile (the dynamic compressive strength was 32–44 MPa), which can reach more than 100 MPa. The maximum electron temperature, electron density, and visible light radiant temperature produced by the hypervelocity impact increase with an increase in impact velocities and target thicknesses, respectively.

Generating Optimized Trajectories for Robotic Spray Painting

In the manufacturing industry, spray painting is often an important part of the manufacturing process. Especially in the automotive industry, the perceived quality of the final product is closely linked to the exactness and smoothness of the painting process. For complex products or low batch size production, manual spray painting is often used. But in large scale production with a high degree of automation, the painting is usually performed by industrial robots. There is a need to improve and simplify the generation of robot trajectories used in industrial paint booths. A novel method for spray paint optimization is presented, which can be used to smooth out a generated initial trajectory and minimize paint thickness deviations from a target thickness. The smoothed out trajectory is found by solving, using an interior point solver, a continuous non-linear optimization problem. A two-dimensional reference function of the applied paint thickness is selected by fitting a spline function to experimental data. This applicator footprint profile is then projected to the geometry and used as a paint deposition model. After generating an initial trajectory, the position and duration of each trajectory segment are used as optimization variables. The primary goal of the optimization is to obtain a paint applicator trajectory, which would closely match a target paint thickness when executed. The algorithm has been shown to produce satisfactory results on both a simple 2-dimensional test example, and a non-trivial industrial case of painting a tractor fender. The resulting trajectory is also proven feasible to be executed by an industrial robot. <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Note to Practitioners</i> —The work is motivated by the need to generate well performing robot trajectories in robotized spray-painting booths. The described method applies to cases where robotic spray painting is to be used for painting a surface with an even layer of paint at a specified thickness. The method generates and optimizes robot trajectories and is shown to be able to generate a satisfactory paint cover for simple test cases as well as more realistic industrial cases. For a user it could be implemented as is, or be obtained as a standalone service, but there are some prerequisites that need to be fulfilled to make use of the optimization method. It is assumed that the surface to be painted is available as a CAD-model and that physical testing has been performed to determine the characteristics of the paint and nozzle. These physical tests amount to spraying paint on a flat piece of material at a few different distances from the surface and measuring the cross section of the paint thickness. The resulting trajectory can be executed on any industrial painting robot that can handle linear motion commands.

Production cross sections of samarium-153 and -145 via alpha-particle-induced reactions on natural neodymium

Production cross sections of 153,145Sm via alpha-particle-induced reactions on natNd were measured up to 23 MeV. The stacked-foil activation technique and high-resolution gamma-ray spectrometry were adopted for the measurement. The obtained cross sections were compared with the literature data and the TENDL-2019 and TENDL-2021 values. Physical thick target yields of the two radionuclides were derived from the measured cross sections.

Hints of quasi-molecular states in 13B via the study of 9Li-4He elastic scattering

This paper reports on elastic scattering excitation functions for the reaction 9Li+4He measured at backward angles in the centre of mass energy range 5 MeV ≤ E≤c.m.9.5 MeV, with the aim of investigating the possible existence of molecular resonances which have been predicted to exist in the case of neutron-rich B-isotopes. Due to the short lifetime of 9Li, the experiment necessitated the use of inverse kinematics on a gaseous 4He target. The Thick Target Inverse Kinematics technique was used which allowed for the measurement of the full excitation function in a single 9Li run. Broad resonances were observed in the excitation region for 13B 15 MeV ≤ Ex≤20 MeV. To understand the nature of such broad structures, various theoretical attempts are reported concerning possible reaction mechanisms for this neutron rich reaction. The most promising approach to interpret the data is within the orbiting reaction scenario.

Production of 230Pa as a Source for Medical Radionuclides 230U and 226Th Including Isolation by Liquid–liquid Extraction

ABSTRACT Liquid–liquid extraction of protactinium with different extractants (1-octanol, MIBK, aliquat 336) was studied depending on concentration of nitric and hydrochloric acids, presence of bulk amount of thorium, fluoride ions, and addition of boric acid or Al3+ ions as a masking agent. The extraction with 1-octanol followed by back-extraction with 7 M HCl + 0.1 M HF solution proved to be appropriate for selective 230Pa isolation from thorium irradiated with medium-energy protons. The proposed procedure provided simultaneous production of medical 225Ac and 230Pa/230U from the same Th-target. The experimental cross-sections of 230Pa formation in the reaction 232Th(p,3n)230Pa were determined for the protons energy range of 140–35 MeV and compared with literature data. The yield of 230U and impurities of 232U and 233U depending on the energy of protons entering a thick thorium target were estimated.

Efficiency of 124I radioisotope production from natural and enriched tellurium dioxide using 124Te(p,xn)124I reaction

Background124I Iodine (T_{1/2} = 4.18 d) is the only long-life positron emitter radioisotope of iodine that may be used for both imaging and therapy as well as for 131I dosimetry. Its physical characteristics permits taking advantages of the higher Positron Emission Tomography (PET) image quality, whereas the availability of new molecules to be targeted with 124I makes it a novel innovative radiotracer probe for a specific molecular targeting.ResultsIn this study Monte Carlo and SRIM/TRIM modelling was applied to predict the nuclear parameters of the 124I production process in a small medical cyclotron IBA 18/9 Cyclone. The simulation production yields for 124I and the polluting radioisotopes were calculated for the natural and enriched 124TeO2 + Al2O3 solid targets irradiated with 14.8 MeV protons. The proton beam was degraded energetically from 18 MeV with 0.2 mm Havar foil. The 124Te(p,xn)124I reactions were taken into account in the simulations. The optimal thickness of the target material was calculated using the SRIM/TRIM and Geant4 codes. The results of the simulations were compared with the experimental data obtained for the natural TeO2 +Al2O3 target. The dry distillation technique of the 124-iodine was applied.ConclusionsThe experimental efficiency for the natural Te target was better than 41% with an average thick target (>0.8 mm) yield of 1.32 MBq/μAh. Joining the Monte Carlo and experimental approaches makes it possible to optimize the methodology for the 124I production from the expensive Te enriched targets.

Optimization of target thickness and investigation on the effect of heat treatment on the ballistic performance of aluminium alloy 7075 targets against hard steel core projectile

Optimization of target thickness and influence of heat treatment condition on the high velocity impact response of aluminium alloy 7075 targets have been determined. Both experimental and numerical studies were conducted using a 7.62 mm hard steel core projectile. The numerical simulation used a 7.62 mm Ogival nose shaped projectile with a target thickness ranging from 20 to 26 mm. High velocity impact experiments on T651 and solution treated targets, with rolled plate thicknesses ranging from 21 to 25 mm were carried out to validate the numerical findings. The microhardness of the targets was measured using Vicker's microhardness tester and fractographs were examined using a scanning electron microscope. The projectile penetrated regions were analyzed using light microscopy. A good correlation between the numerical and experimental ballistic behaviour of aluminium alloy 7075 targets was observed and an optimum target thickness of 21 and 24 mm was observed for the T651 and solution treated targets to prevent the projectile's penetration. It was also noted that, after the projectile's impact, solution treated targets had higher microhardness compared to T651 condition targets. This is due to higher work hardening of solution treated targets near the penetration channel. Even though T651 targets have a lower depth of penetration compared to solution treated targets, ‘splintering’ failure of the T651 targets is observed. In contrast, ‘petalling’ and ‘plugging’ kinds of failures were noticed on the solution treated targets. Thus, solution treatment of ballistic targets may enhance the ballistic limit of armoured vehicles.

Design and optimization of thin-film tungsten (W)-diamond target for multi-pixel X-ray sources.

Emerging multi-pixel X-ray source technology enables new designs for X-ray imaging systems. The power of multi-pixel X-ray sources with a fixed anode is limited by focal spot power density. The purpose of this study is to optimize the W-diamond target and predict its performance in multi-pixel X-ray sources. X-ray intensity and energy deposition in the W-diamond target with different thicknesses of tungsten film and incident electron energies was calculated with the Geant4 Monte Carlo toolkit. COMSOL Multiphysics software was used to analyze the transient and stationary heat transfer in the thin-film W-diamond target. The maximum tube power and X-ray output intensity were predicted for both transmission and reflection target configurations. The maximum focal spot power density was limited by either the graphitization of the diamond substrate or the melting point of the W target. With optimal W-target thickness, the maximum transmission X-ray intensities are about 40%-50% higher than the maximum reflection intensities. Thin-film W-diamond targets allow four to five times more maximum power input and produce six to seven times higher transmission X-ray intensity in continuous mode compared with conventional reflection W thick targets. Depending on the focal spot size, reducing the X-ray pulse duration can further enhance the tube power. Multi-pixel X-ray sources using this W-diamond target design can produce significantly higher X-ray output than traditional thick tungsten targets without major modification of the tube design.

Failure and fragmentation of ceramic target with varying geometric configuration under ballistic impact

The failure and fragmentation of monolithic bare alumina 99.5% ceramic target and energy dissipation of steel 4340 projectile have been studied in a series of ballistic experiments carried out, with the incidence velocities in a range, 122–290 m/s. The velocity drop and energy dissipation increased with incidence velocity for 10 mm thick target with damage zone extended upon the whole area of rear face at higher velocities. The ballistic results obtained with the 10 mm thick target have been compared with the ballistic performance of the 5 mm thick target used in a previous study to explore the effects of target thickness on the failure mechanism. A model for the residual velocity of projectile after perforation of the single layered ceramic target has been developed based on the Lambert Jonas model by using the experimental data available for 5 mm and 10 mm thick alumina 99.5% target against 10.9 mm projectile. The residual velocities and damage patterns were reproduced with a reasonable amount of accuracy by a three-dimensional finite element model developed on commercial ABAQUS/CAE. The effect of obliquity and projectile diameter to target thickness ratio (D/T) on ballistic performance has been determined by the numerical simulation model with impact velocity in a range of 300–500 m/s. A spatial variation of ejected fragments velocity at different time steps was plotted to develop a velocity profile for the ceramic fragments coming out of the target. A semi-empirical model has been proposed for residual velocity after perforation of a monolithic ceramic target, relating to the incidence velocity and projectile diameter to target thickness ratio. The monolithic ceramic targets have been investigated for a comparative assessment of energy dissipation by the ceramic layer to eventually design an efficient front layer of a ceramic based composite armour in future studies.

Electron-positron pairs and radioactive nuclei production by irradiation of high-Z target with γ -photon flash generated by an ultra-intense laser in the λ3 regime

This paper studies the interaction of laser-driven $\ensuremath{\gamma}$ photons and high-energy charged particles with high-Z targets through Monte Carlo simulations. The interacting particles are taken from particle-in-cell simulations of the interaction of a tightly focused ultra-intense laser pulse with a titanium target. Lead is chosen as the secondary high-Z target because of its high cross-section of the giant dipole resonance and electron-positron pair production. The results reveal an ultra-short, ultra-relativistic collimated positron population and their energy spectra, angular distribution, and temporal profile are found. We investigate the target thickness dependence of the resulting total numbers and total kinetic energies of various particle species emitted from the lead target irradiated with laser-generated $\ensuremath{\gamma}$ photons and charged particles separately. We plot the charts of residual high-Z nuclides generated by irradiation of the lead target. Because of the short pulse duration, the $\ensuremath{\gamma}$ photon, electron-positron, and neutron sources could find applications in material science, nuclear physics, laboratory astrophysics, and as injectors in laser-based accelerators of charged particles.

Design optimization of an electron-to-photon conversion target for ultra-high dose rate x-ray (FLASH) experiments at TRIUMF

Objective. To develop a bremsstrahlung target and megavoltage (MV) x-ray irradiation platform for ultrahigh dose-rate (UHDR) irradiation of small-animals on the Advanced Rare Isotope Laboratory (ARIEL) electron linac (e-linac) at TRIUMF. Approach. An electron-to-photon converter design for UHDR radiotherapy (RT) was centered around optimization of a tantalum–aluminum (Ta–Al) explosion-bonded target. Energy deposition within a homogeneous water-phantom and the target itself were evaluated using EGSnrc and FLUKA MC codes, respectively, for various target thicknesses (0.5–1.5 mm), beam energies (E e− = 8, 10 MeV) and electron (Gaussian) beam sizes ( = 2–10 mm). Depth dose-rates in a 3D-printed mouse phantom were also calculated to infer the compatibility of the 10 MV dose distributions for FLASH-RT in small-animal models. Coupled thermo-mechanical FEA simulations in ANSYS were subsequently used to inform the stress–strain conditions and fatigue life of the target assembly. Main results. Dose-rates of up to 128 Gy s−1 at the phantom surface, or 85 Gy s−1 at 1 cm depth, were obtained for a 1 × 1 cm2 field size, 1 mm thick Ta target and 7.5 cm source-to-surface distance using the FLASH-mode beam (E e− = 10 MeV, 2 = 5 mm, P = 1 kW); furthermore, removal of the collimation assembly and using a shorter (3.5 cm) SSD afforded dose-rates >600 Gy s−1, albeit at the expense of field conformality. Target temperatures were maintained below the tantalum, aluminum and cooling-water thresholds of 2000 °C, 300 °C and 100 °C, respectively, while the aluminum strain behavior remained everywhere elastic and helped ensure the converter survives its prescribed 5 yr operational lifetime. Significance. Effective design iteration, target cooling and failure mitigation have culminated in a robust target compatible with intensive transient (FLASH) and steady-state (diagnostic) applications. The ARIEL UHDR photon source will facilitate FLASH-RT experiments concerned with sub-second, pulsed or continuous beam irradiations at dose rates in excess of 40 Gy s−1.

Analytical Investigation of Ricochet Range of Ogive—Shaped Nose Projectile Obliquely Penetrating Thick Steel Target

The ricochet phenomenon has been studied worldwide for a long time in consideration of its significance in ballistics. A ricochet projectile has proven to be worthless to its launcher, as warheads fail to penetrate the interior of targets and strike the facilities and personnel of enemies effectively. A large portion of related research has been dedicated to avoiding ricocheting, which mainly focuses on improving the penetration ability of a projectile in order to obtain a better penetration effect, while investigations on the proactive protection of key targets from damage caused by a ricochet projectile are minor. This study analytically explores the ricochet range of a projectile obliquely penetrating a thick steel target. Firstly, the moment of momentum equation of the ricochet projectile based on theoretical mechanics is utilised to analytically calculate its trajectory, where a mathematical model of a two-stage ricochet impacting is established through the geometrical analysis of the ricochet process for determining the ricochet range of a projectile and the size of the bulletproof structure. Then, impact experiments of a projectile obliquely penetrating thick steel targets at different striking velocities and inclination angles are carried out, and the influences of the striking velocity and angle of attack on the damage pattern, area and penetration depth are discussed to identify the ricochet phenomenon. Moreover, the deflection angle of the ricochet projectile is computed, which is compared with the experimental measurements in order to validate the accuracy of this proposed model. This proposed research may promote security protection during live-firing training and provide a theoretical foundation for the optimisation of purposeful protection.

A concept for the extraction of the most refractory elements at CERN-ISOLDE as carbonyl complex ions

We introduce a novel thick-target concept tailored to the extraction of refractory 4d and 5d transition metal radionuclides of molybdenum, technetium, ruthenium and tungsten for radioactive ion beam production. Despite the more than 60-year old history of thick-target ISOL mass-separation facilities like ISOLDE, the extraction of these most refractory elements as radioactive ion beam has so far not been successful. In ordinary thick ISOL targets, their radioisotopes produced in the target are stopped within the condensed target material. Here, we present a concept which overcomes limitations associated with this method. We exploit the recoil momentum of nuclear reaction products for their release from the solid target material. They are thermalized in a carbon monoxide-containing atmosphere, in which volatile carbonyl complexes form readily at ambient temperature and pressure. This compound serves as volatile carrier for transport to the ion source. Excess carbon monoxide is removed by cryogenic gas separation to enable low pressures in the source region, in which the species are ionized and hence made available for radioactive ion beam formation. The setup is operated in batch mode. Initially, we investigate the feasibility of the approach with isotopes of more than 35s half-life. At the cost of reduced efficiency, the concept could also be applied to isotopes with half-lives of at least one to 10s. We report parameter studies of the key processes of the method, which validate this concept and which define the parameters for the setup. This would allow for the first time the extraction of radioactive molybdenum, tungsten and several other transition metals at thick-target ISOL facilities.

Study on explosion resistance process simulation and blast fracture failure of Ti[sbnd]6Al[sbnd]4V titanium alloy sheet

The application of high-strength and high-toughness titanium alloy in armour protection is increasing with its excellent properties. However, there is little research on titanium alloy in explosion protection, especially the dynamic response process under localised explosion load and finite element simulation of the explosion resistance process of titanium alloy sheet. In this paper, the deformation and fracture failure features of the 1.6 mm thick Ti6Al4V titanium alloy sheet during the blast loading process were studied by combining LS-DYNA finite element simulation and air explosion experiments. The error of the overpressure peak value of explosion shock wave between the value obtained by improved theoretical empirical formula calculation of cylindrical charge and the value obtained by numerical simulation is only 0.2%. By studying the influence of explosive shape and air domain mesh size on the overpressure value in the process of detonation wave propagation, the Structured Arbitrary Lagrangian-Eulerian (S-ALE) algorithm was selected for finite element simulation. When the air domain mesh size is 1 mm, the tensile failure criterion was introduced into the finite element simulation process. The results show that the numerical simulation results of the full-scale model and the test results were consistent. The destruction morphology of the target showed severe asymmetry. Under 50 g TNT blast load, the 1.6 mm thick Ti6Al4V titanium alloy target was damaged seriously, and the central area of the target was completely torn. The failure features were mainly petal-shaped warping tearing cracks and localised plastic deformation. The tensile stress is the main stress mode of the target failure. Therefore, dynamic tensile strength should be used as one of the selection criteria for explosion-resistant titanium alloy sheets. The target failure mode is dominated by adiabatic shear fracture.

New experimental data on natDy(a,x) reactions: Details on the production of the medically relevant 161Er, 160Er, and 161Ho Auger emitters

The cross sections for the formation of 160Er, 161Er, 162mHo, 157Dy in nuclear reactions natDy(α,x) in the energy range 53 → 20 MeV were measured by the stacked foils method. Most of the data were obtained for the first time. A comparison of the data with simulation results from the TENDL-2019 library is given. The 161Er yield on a thick target is 88.4 MBq/µAh. The natDy(α,x)161Er → 161Ho route was studied for 161Ho production. The possibility to produce 161Ho in an amount sufficient for medical applications was shown. The main radioisotope impurity is 160m,gHo (in the amount of 3–6% in terms of activity). The thick target yield of 160Er is 2.16 MBq/µAh, which is significantly less than those of the reactions induced by protons and deuterons.

Measurement of the natDy(p,x) nuclear reactions cross-sections

Excitation functions of the reactions natDy(p,x)159m+gHo, 161m+gHo, 162mHo, 162gHo, 155m+gDy, 157m+gDy, 159m+gDy, 155Tbcum, 155Tb, 156Tbcum, 160Tb, 161Tb, 159m+gGd were measured in the energy range of 7.4–35.9 MeV using the stacked foil technique and off-line γ-ray spectrometry. The obtained cross-sections were compared with previously published experimental data and prediction of the TALYS nuclear reaction model code adopted from the TENDL-2019 library. Thick target yields were calculated from the experimental data.