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Neutron activated concrete reference material for measurement of residual radioactivity by gamma-ray spectrometry has been prepared. The main radionuclides were 60Co, 152Eu, 54Mn, 154Eu and 134Cs. One-way ANOVA homogeneity test has shown that the samples are homogeneous. The activity concentrations of 54Mn, 59Fe, 154Eu and 134Cs were relatively low; only 60Co activity concentration was found to be higher therefor it was considered as the main target isotope. The prepared sample can be used as a tool to prove compliance to radiation protection and environmental regulations during decommissioning of cyclotron buildings or other irradiation facilities that produce residual radioactivity. [ABSTRACT FROM AUTHOR]

We are developing a high-current cyclotron as a driver for the IsoDAR neutrino experiment. It accelerates 5 mA of H2+ to 60 MeV/amu, after which the electron is removed to produce a 10 mA, 60 MeV proton beam. The enabling innovations that offset space-charge effects occur at injection and in the first few turns, allowing one to construct cyclotrons with energies ranging from below 5 MeV up to 60 MeV/amu, or possibly higher, with the same performance for accelerated ions with Q/A = 0.5 (H2+, D+, He++, ...). In this paper, we discuss the possible uses of such cyclotrons for isotope production, including production of long-lived generator parents (68Ga, 44Ti, 82Sr,...), as well as intense fast neutron beams from deuteron breakup for (n,2n) production of isotopes like 225Ac. [ABSTRACT FROM AUTHOR]

The implementation of the Variable Energy (VE) feature in the previously fixed-energy IBA Cyclone® Kiube cyclotron is presented as an upgrade enabling the production of novel radioisotopes with improved radionuclidic purity and production yields. The possibility of easily decreasing the energy of the extracted proton beam, from 18 down to 13 MeV, allows us to avoid the use of degraders and/or thick target windows, thus preventing related beam current limitations. The immediate application of the Variable Energy feature is proven by presenting the improved results obtained for the production of 68Ga from the irradiation of liquid targets simultaneously in terms of radionuclidic purity and activity produced. [ABSTRACT FROM AUTHOR]

Introduction: Hadron therapy is today an established modality in cancer radiation therapy that, world-wide, is available in about hundred centres. About 90% of them are devoted to proton therapy and the rest also to carbon ion therapy. Based on the superior ballistic and radiobiological properties of fast ions, this discipline experienced a remarkable growth in the last 30 years. Purpose: This paper reviews the history of hadron therapy starting from the initial work done at Berkeley in the 30's. Methods: Fast neutron therapy is not forgotten but the main accent is on the parallel development of proton and carbon ion therapy. For space reasons pion therapy, to which a lot of efforts have been devoted without success, is not discussed. Results: The activities of the main protagonists in USA, Japan and Europe are shortly presented so that the reader can appreciate the relevance of the contribution given by each of them to the advancement of the field. Conclusions: The review ends in 2005, when the carbon ion centres HIT in Heidelberg and CNAO in Pavia were under construction, with the aim of putting at the disposal of European citizens advanced treatments of radioresistant tumours, which cannot be effectively treated neither with X rays nor with protons. [ABSTRACT FROM AUTHOR]

The neutron activation of stable isotopes in environmental matrices, such as soil and groundwater, is a critical aspect of assessing the impact of radionuclide production facilities on the surrounding ecosystem. The envisioned Low-Energy Radioactive Ion Beams (LERIB) facility at the iThemba LABS, South Africa is anticipated to generate significant sources of ionising radiation. The study investigated the possible repercussions of neutron irradiation stemming from the facility, focusing on the activation of stable isotopic compositions in the environment. The investigation employed a combination of experimental and analytical techniques to characterize the neutron activation products in soil and groundwater samples collected from the vicinity. Samples were collected from designated areas for background radiological measurements and were irradiated with neutrons for a period of 1 h. The induced radioactivity measured by the High Purity Germanium detector included 24Na, 22Na, 54Mn, 52Mn, and 46Sc. The application of Darcy’s law for groundwater velocity suggests that radionuclides in groundwater will migrate at an average flow velocity of 0.8 m/day. The isotopes with longer half-lives have count rates at background concentrations; therefore, environmental impacts on the site and surrounding communities might be minimal. [ABSTRACT FROM AUTHOR]

The present work promotes and validates the benefits of using niobium instead of Havar® as the material for the target windows in most routine irradiations in cyclotrons. Calculation of the material activation and measurements of the contamination of the transferred target liquids show major improvements with the use of niobium. Also, the data of the daily routine productions at our production center are presented, proving that Havar® is not mandatory unless large target currents and/or pressures are required. [ABSTRACT FROM AUTHOR]

The precise measurement and error compensation technique of the main magnetic field in cyclotron accelerator are important research directions and key components in the construction of the device. Due to factors such as internal defects in the iron material and mechanical processing errors, the non-ideal magnetic field generated by the main magnet of the cyclotron accelerator usually deviates from the required isochronous magnetic field distribution and contains a certain amplitude of harmonic magnetic field. Therefore, in the process of developing a cyclotron accelerator, it is necessary to perform multiple shimming on the non-ideal magnetic field, and ultimately achieve the required distribution by correcting the actual magnetic field. Compared with traditional magnetic field compensation algorithms, this paper proposes an algorithm based on a multivariate linear regression model, incorporating the calculation of the first harmonic magnetic field. This algorithm achieves simultaneous quantitative shimming for both temporal errors in the magnetic field and first harmonic errors, eliminating the need for a separate iterative process for shimming the first harmonic magnetic field. In order to avoid increasing the finite element calculation workload, this paper uses a 1/4 magnet model in the new algorithm to obtain the shape function for the first harmonic magnetic field and the average magnetic field. Simplifying the full model finite element calculation of the main magnet to a 1/4 model can save approximately 80% of CPU time. By using the algorithm proposed in this paper, after three iterations of shimming, the isochronism error of the magnetic field in the 16 MeV cyclotron at the China Institute of Atomic Energy is reduced to the order of 10-4, and the integral sliding phase control of particles is controlled within ±14°, while the magnitude of the first harmonic of the magnetic field is reduced to within 6 Gs. The transverse free oscillation frequency of the magnetic field was also adjusted, improving the axial focusing frequency at large radius positions, allowing the beam to pass through dangerous resonances only at low energy positions and quickly move away from resonance positions. Through the first shimming process, the magnitude of the first harmonic of the magnetic field is reduced, minimizing the coupling of the beam phase space in the transverse direction and avoiding major harmful resonances. Experimental studies have shown that this algorithm has the characteristics of low computational cost for shape function calculations, high shimming accuracy, and a small number of iterations. The algorithm in this article can be further expanded to realize the shimming calculation of any high-order harmonic magnetic field error of the cyclotron.

The ion source is one of the key devices for the high-intensity cyclotron, which exerts influence on the beam intensity and applications of the machine. As part of the cyclotron research and development effort, China Institute of Atomic Energy (CIAE) has been developing arc discharge H- ion sources based on volume production and multi-cusp magnetic configuration since 1997. In 2000, 5.2 mA H- beam was reached and 15 mA H- beam was achieved in 2010. After a long break, H- ion source development started again in 2022 in order to improve performance of the main H- ion source of the CIAE 18 MeV cyclotron and to fulfill the requirement of future other high intensity proton beam cyclotrons for the high intensity H- ion. A new H- ion source and test stand was built at CIAE in 2023. The design of this new ion source was based on the experience on our previous 15-20 mA H- ion source and the source at TRIUMF. Major efforts included the study of the virtual filter magnetic field for filtering out fast electrons, multi-cusp confining magnetic field, four-half-circle ring filaments length and location, improvement of extraction structure and upgrading of vacuum system and power supplies. Up to now, more than 21 mA of H- beam were obtained at a high voltage of 35 kV from a plasma electrode hole of 13 mm in diameter when the hydrogen flux was 25 sccm. At this output the maximum arc power available is only 4.5 kW and the e/H- ratio is about 5. When the hydrogen flux is higher or extraction high voltage is higher, H- beam currents can reach 22 mA. However, the H- beam is very unstable with terrible sparks at extraction and acceleration gaps in this case, about five times a minute. This appears to be due to the lack of a differential pumping structure, which also results in an unexpectedly high hydrogen flux. In the experiment, the relationship between arc power and H- beam intensity was determined, also the optimal location of the four-filament structure was determined, which is obviously related to the virtual filter magnetic field distribution. At present, the emittance scanner is being processed and the measurement program is also updated and improved, the beam emittance has not been measured and analyzed at this stage. Subsequently, the vacuum chamber structure will be improved, the extraction structure also will be optimized to obtain brighter H- beam, and a long-lasting filament will be developed to reduce maintenance time.

Copyright of Atomic Energy Science & Technology is the property of Editorial Board of Atomic Energy Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Atomic Energy Science & Technology is the property of Editorial Board of Atomic Energy Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Isotopes is the property of Journal of Isotopes Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Four-dimensional visualization, i.e., three-dimensional space plus time, of fluid flow and its interactions in geological materials using positron emission tomography (PET) requires suitable radiotracers that exhibit the desired physicochemical interactions. 76Br is a likely candidate as a conservative tracer in these studies. [76Se]CoSe was produced and used as the target material for the production of 76Br via the (p,n) reaction at a Cyclone 18/9 cyclotron. 76Br was separated from the target by thermochromatographic distillation using a semi-automated system, combining a quartz glass apparatus with a synthesis module. 76Br was successfully produced at the cyclotron with a physical yield of 72 MBq/µAh (EOB). The total radiochemical yield of 76Br from the irradiated [76Se]CoSe target (EOS) was 68.6%. A total of 40 MBq–100 MBq n.c.a. 76Br were routinely prepared for PET experiments in 3 mL 20 mM Cl− solution. The spatial resolution of a PET scan with 76Br in geological materials was determined to be about 5 mm. The established procedure enables the routine investigation of hydrodynamics by PET techniques in geological materials that strongly sorb commonly used PET tracers such as 18F. [ABSTRACT FROM AUTHOR]

Locally inclined targets are developed to produce medical radioisotopes which can be used for high-intensity proton beam irradiation. The results of a numerical analysis of thermal processes in locally inclined targets made of pressed molybdenum powder with a niobium target holder for the Nirta Solid Compact Model TS06 target module are presented. Computations were carried out using the Fluid Flow (Fluent) engineering package of the ANSYS Workbench 18.2 software platform for variants of targets with linear and axially symmetric grooves in the proton irradiation zone. It has been shown that using various models of locally inclined targets with a cooling area increased by 2.37 times, it is possible to increase the irradiation current by 1.34–1.46 times compared to a standard flat target. An analysis of the distribution of heat flows and temperatures in the targets was also carried out. [ABSTRACT FROM AUTHOR]

Previous efforts to investigate changes in the decay constants of radioactive nuclides discovered that solar flares can temporarily alter radioactive decay rates. Thus, discerning whether external factors affect radioactive decay rates is vital for understanding nuclear processes. This study sought to explore the effect of neutrinos on radioactive nuclei by constructing a gamma radiation detection system that employs a radioactive source in front of a neutrino emission system. Responding to cyclotron operations, each of the four detection systems registered gamma count rate decreases. The results of this study confirm that rises in neutrino flux affected the decay rates of the examined radioactive nuclides. Here we provide significant evidence that neutrinos affect the radioactive decay process. Neutrino detection is challenging due to the minuscule absorption in a stable nucleus. However, the study found a greater probability of radionuclides interaction with the neutrino.

The article deals with the problem of formation of undesirable β-emitting radionuclides (RNs) in the production of radiopharmaceuticals for PET diagnostics. It is found that tritium is the main trace RN formed by the reaction 18O(p,t)16O during irradiation of water [18O]H2O with protons. Other trace β emitters in water accumulate mainly as a result of leaching of activated target wall materials. The possibility of using the activity of tritium in water [18O]H2O as an indicator of its re-enrichment is shown. The necessity of controlling the content of trace β-emitting RNs in intermediate products, production waste, and final radiopharmaceuticals is demonstrated. [ABSTRACT FROM AUTHOR]

An experimental complex was created at the NRC Kurchatov Institute for testing of structural materials developed for MSR. The complex makes it possible to implant helium and (or) hydrogen into material specimens at the U-150 cyclotron, simulating the result of long-term neutron exposure, to perform mechanical tests and microstructural studies before and after simulation exposure, and to test the compatibility of structural materials before and after exposure with fuel salt in non-isothermal dynamic conditions at temperatures up to 750°C with control of the melt redox potential. Preliminary tests with samples of nickel-molybdenum alloy KhN80MT demonstrated the efficiency of the proposed experimental technique. The concentration of helium nuclei in the alloy samples reaches ~150 ppm for approximately 10 h of irradiation. [ABSTRACT FROM AUTHOR]

This article provides data on the development and creation of a vacuum window module, which will bring out the proton beam of the C18 cyclotron (IBA, Belgium) with energy of 18 MeV from a vacuum environment into the atmosphere. The module is made of aluminum and consists of a flange with a collimator and a helium (He) chamber of foil plates cooling. The module was installed at the end of the cyclotron's beam line. Profile measurements were made for various current values of proton beam from 1 to 30 µA. The vacuum window showed its functionality. [ABSTRACT FROM AUTHOR]

Summary: Radiopharmaceutical research and bioscience or medical applications have changed during the decades in the function of available technologies for radioisotope production and imaging detection technologies. In the 1940s to 1960s year, radioisotopes were supplied by reactor production, such as 131I for thyroid uptake study, 197Hg, 203Hg-chlormerodrin for brain scans, 198Au-colloid for liver scans, and 85Sr-chloride for the bone scans. In the late 1960s, with the development of the gamma camera by Hal Anger, and the 99Mo/99mTc generators by researchers of the Brookhaven National Laboratory, the focus was moved to research and diagnostic application of 99mTc radiopharmaceuticals, and these compounds have been in use until now. In that age, the chemistry of technetium, including the production of different chelators and radiolabeling processes, were developed. Cyclotron-producing radioisotopes for medical application emerged in 1955, and for a long time, it was used to produce gamma-emitting radionuclides such as 67Ga, 111In, and 201Tl. After the development of PET câmera around 1975, positron-emitting radioisotopes started to be produced routinely in cyclotrons, such as 11C, 13N, and 18F, gaining market status for diagnostic applications after Alfred Wolf and colleagues developed the 18F-FDG, around 1978. In the following year, positron-emitting radiometals 68Ga, 64Cu, and 89Zr, began to be produced on a large scale to label molecules with short or long circulation times in the body. The results in the specificity of the diagnostic opened the possibility of using 90Y and 177Lu, both beta-emitting radioisotopes, to label the same molecules for therapeutic purposes; thus, theranostics pair 68Ga or 64Cu/90Y or 177Lu started to be used in nuclear medicine. From the 2010s, true theranostic pairs gain interest, such as 44gSc/47Sc, 64Cu/67Cu, 83Sr/89Sr, 86Y/90Y, 124I/131I, 152Tb/161Tb, and 152Tb/149Tb, stated to be produced and evaluated for clinical applications. All these developments in radioisotope production and imaging systems also boosted the development of molecule radiolabeling processes, mainly through automated systems, to ensure speed, reproducibility, and less exposure to professionals involved in preparing these molecules. Furthermore, several chelating agents have been developed to complex different metals in a simple, effective, and stable way, such as the DOTA, NOTA, HBED molecules, among others. Conclusão: Trends in radioisotopes and radiolabeling methods result from scientific and technological developments in different areas but with congruent purposes. The result is a large number of products that can be chosen by their physical, chemical, biological, or economic characteristics.

Abstract Background Radiopharmaceuticals capable of targeting the fibroblast activation protein have become widely utilized in the research realm as well as show great promise to be commercialized; with [68Ga]Ga-FAPI-46 being one of the most widely utilized. Until now the synthesis has relied on generator-produced gallium-68. Here we present a developed method to utilize liquid-target cyclotron-produced gallium-68 to prepare [68Ga]Ga-FAPI-46. Results A fully-automated manufacturing process for [68Ga]Ga-FAPI-46 was developed starting with the 68Zn[p,n]68Ga cyclotron bombardment to provide [68Ga]GaCl3, automated purification of the [68Ga]GaCl3, chelation with the precursor, and final formulation/purification. The activity levels produced were sufficient for multiple clinical research doses, and the final product met all release criteria. Furthermore, the process consistently provides 40 mCi (> 1480 MBq) of [68Ga]Ga-FAPI-46 in excellent radiochemical yield was achieved with all batches meeting release criteria.

The implementation of the Variable Energy (VE) feature in the previously fixed-energy IBA Cyclone® Kiube cyclotron is presented as an upgrade enabling the production of novel radioisotopes with improved radionuclidic purity and production yields. The possibility of easily decreasing the energy of the extracted proton beam, from 18 down to 13 MeV, allows us to avoid the use of degraders and/or thick target windows, thus preventing related beam current limitations. The immediate application of the Variable Energy feature is proven by presenting the improved results obtained for the production of 68Ga from the irradiation of liquid targets simultaneously in terms of radionuclidic purity and activity produced.

A high-accuracy magnetic field measurement device based on a cyclotron is being developed for accelerator mass spectrometry (AMS). In this study, a magnetic field measurement device consisting of a Hall probe sensor, piezo-motor, and step motor was developed to measure the magnetic field of the AMS cyclotron magnet. The Hall probe sensor was calibrated to achieve positional accuracy by using polar coordinates. The measurement results between the ratchet gear and piezo-motor, which are the instruments used for driving the measurement device, were analyzed. The measurement result of the device with a piezo-motor exhibits a difference of 5 Gauss (0.04%) as compared with the simulation result.

An electric dipole magnet quite similar to that of the IRANCYC10 cyclotron was designed and constructed to conduct the initial tests on the internal Penning ion source to be installed in the cyclotron. This magnet which was designed and constructed in the department of physics, University of Tehran, is capable of producing a magnetic field of 7000 G in the location of the source, a region in the center of the magnet with the radial extent of 15 mm, with no need for cooling. Magnetic fields as high as 1.1 T are also accessible for a few minutes. The ion source in IRANCYC10 is expected to be exposed by a magnetic field of 1100 G. The measurements show that the magnetic field in the location of the source is homogeneous with the maximum deviation value of 1.1% with respect to the magnetic field strength at the center. The magnet is H type with 100 mm pole diameter and 60 mm gap size. Comsol, Ansys Maxwell and SolidWorks codes were employed in the design and construction of the electric dipole magnet.

In this manuscript, production of 201TlCl, one of the radiopharmaceuticals used in the field of nuclear medicine for diagnostic purposes in heart, muscle, thyroid gland imaging, and cancer diagnosis, at Turkish Energy Nuclear and Mineral Research Agency is described. The production process starts with a cyclotron type proton accelerator operated in energy range of 15–30 MeV with beam intensities up to 1200 μA currently available at the facility. The production is detailed along with the main lines in the other steps. In addition to the radiopharmaceutical productions carried out according to international standards at the facility, new projects are planned in the short and long terms. [ABSTRACT FROM AUTHOR]

68Ga-based radiopharmaceuticals are routinely used for PET imaging of multiple types of tumors. Gallium-68 is commonly obtained from 68Ge/68Ga generators, which are limited in the quantity of activity produced. Alternatively, gallium-68 can easily be produced on a cyclotron using liquid targets. In this study, we optimized the GMP production of [68Ga]GaFAPI-46 using gallium-68 produced via a standard medical cyclotron using liquid targets. Starting from the published synthesis and quality control procedures described for other 68Ga-based radiopharmaceuticals, we have validated the synthesis process and the analytical methods to test the quality parameters of the final product to be used for routine clinical studies. [68Ga]GaFAPI-46 was successfully produced with high radiochemical purity and yield using an IBA Synthera® Extension module. Gallium chloride was produced on a medical cyclotron using a liquid target with activity of 4.31 ± 0.36 GBq at the end of purification (EOP). Analytical methods were established and validated, meeting Ph. Eur. standards. Full GMP production was also validated in three consecutive batches, producing 2.50 ± 0.46 GBq of [68Ga]GaFAPI-46 at the end of synthesis (EOS), with 98.94 ± 0.72% radiochemical purity measured via radio-HPLC. Quality was maintained for up to 3 h after the EOS. Production of [68Ga]GaFAPI-46 was performed and validated using a standard medical cyclotron with liquid targets. The quality control parameters (e.g., sterility, purity, and residual solvents) conformed to Ph. Eur. and a shelf life of 3 h was established. The activity of [68Ga]GaFAPI-46 produced was substantially higher than the one obtained with generators, enabling a better response to the clinical need for this radiopharmaceutical. [ABSTRACT FROM AUTHOR]

Cyclotrons are one of the most important sources of radionuclides used in biomedical applications. The production of important radionuclides used in single-photon emission tomography techniques such as 123I, 67Ga, 201Tl, and 111In has been based for decades on cyclotrons, typically proton machines with an energy up to 30 MeV. The extraordinary growth of positron emission tomography (PET) has led to the development of new models and to the installation of numerous cyclotrons, typically accelerating protons in the energy range 10 to 20 MeV. These have been used for the production of the main PET radionuclides, namely, 11C, 13N, 15O, and above all, 18F. Recently, their use has been extended to the production of radiometals, like 68Ga, and even to the direct production of 99mTc. Moreover, cyclotrons are a valuable tool for research and for the education of new scientists. This critical review presents the main manufacturers and briefly discusses the characteristics of the models they currently offer on the market. [ABSTRACT FROM AUTHOR]

The RAON (Rare Isotope Accelerator complex for ON-line experiments) is currently in the stage of commissioning under the Rare Isotope Science Project (RISP) launched in 2011. RAON will utilize an advanced rare isotope beams produced with a high power target by the Isotope Separation On-Line (ISOL) facility, aiming to deliver high purity and intense, neutron-rich rare isotope beams to the post-accelerator and experimental facilities. The RAON ISOL facility consists of a target/ion source module surrounded by movable shielding blocks in a bunker, remote handling facilities for the target operation, a pre-mass separator, a RFQ cooler buncher, an EBIS charge breeder, and an A/q separator. The installation and alignment of the ISOL facility were completed in June 2021. The target/ion source module allows us to bombard a thick target with a 70 MeV proton beam of RAON, producing a variety of rare isotope beams. Rare isotope beams extracted from the target/ion source can be transported to a pre-mass separator at energies of up to 60 keV, and will be cooled in a RFQ-CB. Cooled ion beams can be sent to two different experimental facilities, such as a Mass Measurement System and a Collinear Laser Spectroscopy in ISOL experimental hall. Alternatively, for post-acceleration of ion beams, the singly charged ion beam of interest can be bunched to 1 0 8 ions in RFQ-CB and then delivered to the EBIS charge breeder through the EBIS branch system. The preparation of multi charged ion beams for the post-acceleration using the superconducting LINAC of SCL3 will be carried out through the EBIS charge breeder and A/q separator to match the energy of 10 keV/u with A/q < 6 with the requirement of RAON Injector. The first commissioning experiment of the ISOL system started in March 2021 using the 133Cs and 120Sn stable beams produced from the target container combined with the surface ion source and laser Ion source. The stable beam experiments have demonstrated the overall functioning of the RAON ISOL system, and we are planning to carry out the first RI beam test using the SiC target with 70 MeV proton of cyclotron in the coming months. [ABSTRACT FROM AUTHOR]

64Cu and 123I are attracting attention in taking up their role in the development and practical use of PSMA-targeting radiopharmaceuticals. The development of urea-based small molecule PSMA ligands labeled 64Cu and 123I has been progressing steadily with the challenge of obtaining optimal performance as PSMA-targeting radiopharmaceutical for prostate cancer. In this review, the authors provide an overview of recent research projects and future directions for the production of cyclotron-based medical radioisotopes 64Cu and 123I, and their application in the development of urea-based small molecule PSMA ligands labeled 64Cu and 123I as radiopharmaceuticals for prostate cancer. [ABSTRACT FROM AUTHOR]

This study developed a quasi-monoenergetic neutron source (QMN) for the semiconductor device's soft error rate test (SER). Quasi-monoenergetic neutrons are generated by Be(p,n)B99 nuclear reaction with a 1 mm beryllium target and 30 MeV protons from a cyclotron. An 8 mm water in the back of the beryllium target is used for avoiding proton penetration. The neutron spectra simulated by MCNP showed that the peak energy was around 26.5 MeV. The heat flow and mechanical properties are numerically analyzed, and the safe operating conditions are therefore determined.

The present work promotes and validates the benefits of using niobium instead of Havar® as the material for the target windows in most routine irradiations in cyclotrons. Calculation of the material activation and measurements of the contamination of the transferred target liquids show major improvements with the use of niobium. Also, the data of the daily routine productions at our production center are presented, proving that Havar® is not mandatory unless large target currents and/or pressures are required.

Four-dimensional visualization, i.e., three-dimensional space plus time, of fluid flow and its interactions in geological materials using positron emission tomography (PET) requires suitable radiotracers that exhibit the desired physicochemical interactions. 76Br is a likely candidate as a conservative tracer in these studies. [76Se]CoSe was produced and used as the target material for the production of 76Br via the (p,n) reaction at a Cyclone 18/9 cyclotron. 76Br was separated from the target by thermochromatographic distillation using a semi-automated system, combining a quartz glass apparatus with a synthesis module. 76Br was successfully produced at the cyclotron with a physical yield of 72 MBq/µAh (EOB). The total radiochemical yield of 76Br from the irradiated [76Se]CoSe target (EOS) was 68.6%. A total of 40 MBq–100 MBq n.c.a. 76Br were routinely prepared for PET experiments in 3 mL 20 mM Cl− solution. The spatial resolution of a PET scan with 76Br in geological materials was determined to be about 5 mm. The established procedure enables the routine investigation of hydrodynamics by PET techniques in geological materials that strongly sorb commonly used PET tracers such as 18F.

Introduction: Targeted Radionuclide Therapy is used for the treatment of tumors in nuclear medicine, while sparing healthy tissues. Its application to cancer treatment is expanding. In particular, Auger-electron emitters potentially exhibit high efficacy in treating either small metastases or single tumor cells due to their short range in tissue. The aim of this paper is to study the feasibility of a large-scale production of thulium-167, an Auger-electron emitter radionuclide, in view of eventual systematic preclinical studies.Methods: Proton-irradiated enriched erbium-167 and erbium-168 oxides were used to measure the production cross sections of thulium-165, thulium-166, thulium-167, and thulium-168 utilizing an 18-MeV medical cyclotron equipped with a Beam Transport Line (BTL) at the Bern medical cyclotron laboratory. The comparison between the experimental and the TENDL 2021 theoretical cross-section results were in good agreement. Additional experiments were performed to assess the production yields of thulium radioisotopes in the BTL. Thulium-167 production yield was also measured irradiating five different target materials (167Er2O3, 168Er2O3, natTm2O3, natYb2O3, 171Yb2O3) with proton beams up to 63 MeV at the Injector II cyclotron of Paul Scherrer Institute.Results and Discussion: Our experiments showed that an 8-h irradiation of enriched ytterbium-171 oxide produced about 420 MBq of thulium-167 with a radionuclidic purity of 99.95% after 5 days of cooling time with a proton beam of about 53 MeV. Larger activities of thulium-167 can be achieved using enriched erbium-168 oxide with a 23-MeV proton beam, obtaining about 1 GBq after 8-h irradiation with a radionuclidic purity of

Linear gas stopping cells have been used for nearly two decades to slow down projectile fragments at the National Superconducting Cyclotron Laboratory, now the Facility for Rare Isotope Beams, for experiments with low-energy and reaccelerated beams. In order to efficiently stop and rapidly extract light to medium-mass fast ions, a cyclotron gas-stopper has been constructed. It uses a cyclotron-type magnet and a helium-gas filled stopping chamber to slow down the injected beam. RF ion guides transport the stopped ions to the center of the magnet and axially through the bore before acceleration to < 60 keV. Following successful offline tests, the cyclotron stopper was moved to an experimental vault and connected to a new momentum–compression beam line. Beam transport to and into the cyclotron stopper was tested with stable beams. Using 46K fragments, the first successful stopping and extraction of a high-energy beam with the cyclotron stopper was demonstrated. [ABSTRACT FROM AUTHOR]

The production and application of radioisotopes and radiopharmaceuticals is a major peaceful application of nuclear science and technology and has opened new gateways for nuclear medicine in critical human diseases. Advances in the production of radioisotopes via nuclear reactors, accelerators, fission, etc. has facilitated the access to these products for Member States. 99Mo, 131I, 177Lu are among the most essential radioisotopes for nuclear medicine and human health and their production and availability always has been an important theme for professional societies and the International Atomic Energy Agency (IAEA). In the meantime, a large list of theranostic radioisotopes including but not limited to 89Zr, 68Ga, 225Ac, Cu-series, Sc-series, Tb-series etc. has provided a powerful toolbox for clinicians and the IAEA is taking steps to ensure their safe and appropriate application in radiopharmacy. The Agency promotes the production and application routes, including research reactors, cyclotrons, linear accelerators, and other cutting-edge methods, according to international and national guidelines and regulations. The IAEA also conducts activities such as Coordinated Research Projects (CRPs), Technical Meetings (TMs), national/regional training courses and conferences, to support and join forces with international professional societies in the development of human resources and research and development activities. Development of databases and freely available publications for all Member States are other useful means to support Member States in radiopharmaceutical sciences.

Abstract Background The radiometal gallium-68 (68Ga) is increasingly used in diagnostic positron emission tomography (PET), with 68Ga-labeled radiopharmaceuticals developed as potential higher-resolution imaging alternatives to traditional 99mTc agents. In precision medicine, PET applications of 68Ga are widespread, with 68Ga radiolabeled to a variety of radiotracers that evaluate perfusion and organ function, and target specific biomarkers found on tumor lesions such as prostate-specific membrane antigen, somatostatin, fibroblast activation protein, bombesin, and melanocortin. Main body These 68Ga radiopharmaceuticals include agents such as [68Ga]Ga-macroaggregated albumin for myocardial perfusion evaluation, [68Ga]Ga-PLED for assessing renal function, [68Ga]Ga-t-butyl-HBED for assessing liver function, and [68Ga]Ga-PSMA for tumor imaging. The short half-life, favourable nuclear decay properties, ease of radiolabeling, and convenient availability through germanium-68 (68Ge) generators and cyclotron production routes strongly positions 68Ga for continued growth in clinical deployment. This progress motivates the development of a set of common guidelines and standards for the 68Ga radiopharmaceutical community, and recommendations for centers interested in establishing 68Ga radiopharmaceutical production. Conclusion This review outlines important aspects of 68Ga radiopharmacy, including 68Ga production routes using a 68Ge/68Ga generator or medical cyclotron, standardized 68Ga radiolabeling methods, quality control procedures for clinical 68Ga radiopharmaceuticals, and suggested best practices for centers with established or upcoming 68Ga radiopharmaceutical production. Finally, an outlook on 68Ga radiopharmaceuticals is presented to highlight potential challenges and opportunities facing the community.

Objectives While working with cyclotrons used for the production of radiopharmaceuticals, workers can experience significant exposure to the adverse effects of ionizing radiation. The aim of this paper was to determine the typical level of such exposure received by such personnel while servicing cyclotrons. Material and Methods Exposure was assessed using TLD detectors placed in an anthropomorphic phantom, as well as dose meter to determine whole body and eye lens exposure. The phantom was placed in locations receiving the greatest exposure to ionizing radiation during service activities. The time spent by employees during servicing was assessed based on routine visits by service technicians. The obtained results were compared with readings of detectors worn by employees during service activities. Results The highest equivalent doses in the thoracic area were found to be received by the lungs (211.16 μSv/year). In the head and neck area, the highest dose was measured in the eye lens (3410 μSv/year). The effective dose for the whole body was found to be 1154.4 μSv/year, based on the phantom, and 149 μSv per service visit (1192 μSv/year), based on the dose meters carried by the workers. Conclusions Service workers are exposed to significant doses of ionizing radiation, representing a clear radiological protection issue. To reduce exposure to eye lenses, it is recommended to use protective goggles when working with highly-radioactive elements. Int J Occup Med Environ Health. 2022;35(6):753–60

Solid targets and a medical cyclotron were used for the large-scale preparation of 68Ga. The target preparation, proton irradiation of a 68Zn-enriched target, dissolution of the target, separation of 68Ga from zinc, and labelling procedure for the [68Ga]Ga-DOTATOC, [68Ga]Ga-DOTANOC, and [68Ga]Ga-PSMA-11 radiopharmaceutical are presented. The radiopharmaceuticals were prepared with a good manufacturing practices quality of up to 6 GBq of the final product per batch at the end of synthesis (EOS) time. A quality control of 68Ga-labelled tracers showed an acceptable radiochemical purity and stable product at least five hours after the EOS. A separation procedure for the effective separation of 68Ga from an iron interferent was developed. [ABSTRACT FROM AUTHOR]

During the production of 18F, as a result of the interaction of the beam of protons and secondary neutrons with the structural elements of the target body, many radionuclide impurities are created in the cyclotron. As part of this work, we theoretically predicted which isotopes would be activated in the target tantalum or silver bodies. Subsequently, we used gamma spectrometry analysis to verify these predictions. The results were compared with the work of other authors who studied titanium and niobium as materials for making the target body. Tantalum has been evaluated as the most favorable in terms of generating radionuclide impurities during the production of 18F by irradiation of 18O-enriched water in accelerated proton cyclotrons. Only three radionuclides were identified in the tested samples: 181W, 181Hf, and 182Ta with a half-life of fewer than 120 days. The remaining reactions led to the formation of stable isotopes. [ABSTRACT FROM AUTHOR]

In this study, an efficient method for targetry and production of zirconium-89 radioisotope (89Zr) with Cyclone-30 cyclotron was developed. The preparation of a highly pure compressed yttrium oxide target material and design of a target made by copper for better heat transfer was performed. Electrodeposition of target with gold was done to prevent the entry of metallic impurities (copper, zinc and other trace metal elements). Nuclear reaction cross sections for optimization of production with new target and irradiation parameters of the target were evaluated. The prepared 89Zr in the form of [89Zr] Zr-oxalate had high radionuclidic purity (>99.9%) and a low chemical impurity concentration (<0.1 ppm for copper and zinc elements). The yield of 89Zr radioisotope production via the reaction of 89Y(p,n)89Zr was measured to be 77 ± 9.5 MBq/μAh (time of irradiation = 3, the current 20–30 µA). [89Zr] Zr-oxalate specific-activity was in the range 2.319641 × 104–3.479443 × 104 MBq/mmol of Oxalate. [ABSTRACT FROM AUTHOR]

An approximate method for calculating the cadmium ratio of a cyclotron-based thermal neutron radiography system was developed. In this method, the Monte-Carlo code, MCNP6.2, was employed to calculate the neutron capture rates of Au-197, and the cadmium ratio was obtained by computing the ratio of neutron capture rates. From the simulation results, the computed cadmium ratio is reasonably acceptable, and the assumption of ignoring the fast neutron contribution to the cadmium ratio is valid.

Abstract Background 124I Iodine (T $$_{1/2}$$ 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. Results In 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. Conclusions The 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.