In 2011 the ActiWiz code was developed at CERN in order to optimize the choice of materials for accelerator equipment from a radiological point of view. Since then the code has been extended to allow ...for calculating complete nuclide inventories and provide evaluations with respect to radiotoxicity, inhalation doses, etc. Until now the software included only pre-defined radiation environments for CERN's high-energy proton accelerators which were based on FLUKA Monte Carlo calculations. Eventually the decision was taken to invest into a major revamping of the code. Starting with version 3 the software is not limited anymore to pre-defined radiation fields but within a few seconds it can also treat arbitrary environments of which fluence spectra are available. This has become possible due to the use of ~100 CPU years' worth of FLUKA Monte Carlo simulations as well as the JEFF cross-section library for neutrons < 20 MeV. Eventually the latest code version allowed for the efficient inclusion of 42 additional radiation environments of the LHC experiments as well as considerably more flexibility in view of characterizing also waste from CERN's Large Electron Positron collider (LEP). New fully integrated analysis functionalities like automatic evaluation of difficult-to-measure nuclides, rapid assessment of the temporal evolution of quantities like radiotoxicity or dose-rates, etc. make the software a powerful tool for characterization complementary to general purpose MC codes like FLUKA. In this paper an overview of the capabilities will be given using recent examples from the domain of waste characterization as well as operational radiation protection.
Cyclotrons for the production of radiopharmaceuticals have become important tools in modern nuclear medicine. At the end of their lifecycles, such installations have to be dismantled and any ...activated materials must be treated according to the local radiation protection legislation. Using a simulation model, we have developed a non-destructive approach for the radiological characterization of components inside and around an IBA Cyclone 18/9 cyclotron. The methodology is based on software tools developed at CERN (FLUKA Monte Carlo code, ActiWiz and RAW). The simulation results were compared to measurements made using reference samples placed around the cyclotron inside the bunker. Results show a reasonable agreement between simulation and measurements of about a factor of two for a set of 27 reference samples and 11 radionuclides of interest. The origin of this factor has been thoroughly evaluated and opened the door to further investigations leading to possible avenues for improvement.
NA60+ is a fixed target experiment proposed in the framework of the Physics Beyond Colliders programme at CERN. It aims to precisely measure the hard and electromagnetic probes in nuclear collisions. ...Initially proposed for the underground cavern ECN3 with very high beam intensities, the experiment now foresees a location in the EHN1 surface hall which was shown to have a limited impact on the physics performance in spite of a significant reduction of beam intensity and detector size. The potential installation and operation of the experiment with the ion beams from the Super Proton Synchrotron (SPS) has been examined regarding detector integration, beam physics, radiation protection and shielding requirements. The integration of the experiment is considered feasible, but would require a significant reconfiguration of the existing hall infrastructure with regards to shielding and layout.
The code SOLIDUSS is a Monte Carlo based solid-state diffusion software for radiation protection. It was developed to accurately estimate the amount of radionuclides that could escape activated ...material affected by an accidental fire. A desorption model based on the computation of the desorption probability of those radionuclides reaching the surface of an object was introduced to upgrade the software, proven to be a significant improvement with respect to earlier stages of the code.
A set of experiments was performed at CERN to estimate the out-diffusion of radionuclides from activated materials typically used in accelerator environments when exposed to high temperatures. In particular, a 49.3 µm thick Cu foil containing 60Co and a 94 µm thick Al foil with 22Na were exposed to approximately 1000 °C and 600 °C respectively for different time periods. Out-diffusion fractions of 1.5 ± 5.5% for 60Co after 5 h and 22.5 ± 3.1% for 22Na after 4 h were obtained.
A set of SOLIDUSS simulations was carried out replicating the experimental setup and using literature diffusion and desorption activation parameters. The results obtained are in good agreement with the experimental data within error bars. A high sensitivity of the simulation results to changes in the input parameters was observed.
•The SOLIDUSS software has been upgraded to account for the desorption of radionuclides.•The out-diffusion of Na-22 from Al is remarkably higher than that of Co-60 from Cu.•The SOLIDUSS software has been benchmarked against experimental data.
Scandium (Sc) has gained significant interest in nuclear medicine due to its 43Sc, 44g/mSc, and 47Sc radioactive isotopes being suitable for cancer diagnostics and therapy, offering a promising ...avenue for theranostics. Various production methods, including irradiation of enriched or naturally abundant calcium (Ca), titanium (Ti), and vanadium (V) materials with different particle beams, have been investigated to produce 43Sc, 44g/mSc, and 47Sc. However, challenges persist in achieving high molar activity and radiochemical purity for medical applications. The physical isotope mass separation technique presents an alternative, obviating the need for enriched target materials by inherently isolating Sc isotopes during the separation process. Despite recent advancements in Sc mass separation at different facilities, efficiency and yield remain sub-optimal for medical dose production. This study aims to systematically investigate the thermal release kinetics of Sc radionuclides from activated natural titanium foils in tantalum (Ta) environments of ISOL (Isotope Separation On-Line) target units. By elucidating the combination of target material structure and temperature conditions, enhanced release parameters were identified. Maximum Sc release from a non-embossed natTi foil samples was achieved at 1200 °C, for embossed natTi foil samples at 1450 °C and for natV foil samples at 1600 °C, within an hour of reaching the set temperature. These findings offer insights into optimizing the mass separation process to improve the efficiency in Sc radionuclide production for medical applications.
We determined the distribution of activation products inside the magnet coils of a medical cyclotron that has been operational for fifteen years. Besides FLUKA, we based our approach on new software ...tools (RAW and ActiWiz) developed for high-energy accelerators at CERN. A combined analysis of measurements on the coils with Monte-Carlo simulations resulted in a detailed three-dimensional radiological characterisation of the coils. Our results provide the required information for the radiation protection expert to identify the appropriate waste elimination scheme.
•FLUKA modelling of an IBA cyclone 18/9 cyclotron including the liquid and gas targets.•Efficient method to calculate the radiological content inside materials using the software tools RAW and ActiWiz.•Experimental validation of the fluence of secondary particle fields.•Three-dimensional radiological characterisation of materials from accelerators.
The out-diffusion of radionuclides from activated material in case of a fire may represent a non-negligible contribution to the radiological source term of such an event. In order to assess the ...contribution of this phenomenon, a software package has been designed and implemented. In the present document we briefly introduce the numerical treatment used to tackle the problem prior to the explanation of the software’s logic. The document ends with an exemplary simulation and a study carried out to validate the implementation of the algorithm.
The presented tool has been named SOLIDUSS, it is mainly written in C++ and uses a Monte Carlo based approach to simulate the diffusion of radioisotopes within solid materials. It is designed to run coupled with CERN-FLUKA, taking advantage of its geometry kernel to carry out diffusion calculations in arbitrarily complex geometries. The user can provide 3D temperature maps along with many other parameters that allow the program to target a wide range of different scenarios. As results SOLIDUSS provides 3D radionuclide concentration maps as well as the amount of radionuclides out-diffused from the selected materials. So far, this software has undergone numerical validation which will be discussed in this paper. Benchmarking against experimental data is currently ongoing.
•Out-diffusion of radionuclides in case of fire may contribute to its source term.•A software named SOLIDUSS was developed to assess the out-diffusion of isotopes.•SOLIDUSS is Monte Carlo based and runs coupled with CERN-FLUKA.•Diffusion is simulated for arbitrarily complex geometries using a Wiener process.•Radioisotopes can be tracked according to 3-D temperature maps.
AWAKE, the Advanced Proton-Driven Plasma Wakefield Acceleration Experiment, is a proof-of-principle R&D experiment at CERN using a 400GeV/c proton beam from the CERN SPS (longitudinal beam size ...σz=12cm) which will be sent into a 10m long plasma section with a nominal density of ≈7×1014atoms/cm3 (plasma wavelength λp=1.2mm). In this paper we show that by measuring the time integrated transverse profile of the proton bunch at two locations downstream of the AWAKE plasma, information about the occurrence of the self-modulation instability (SMI) can be inferred. In particular we show that measuring defocused protons with an angle of 1mrad corresponds to having electric fields in the order of GV/m and fully developed self-modulation of the proton bunch. Additionally, by measuring the defocused beam edge of the self-modulated bunch, information about the growth rate of the instability can be extracted. If hosing instability occurs, it could be detected by measuring a non-uniform defocused beam shape with changing radius. Using a 1mm thick Chromox scintillation screen for imaging of the self-modulated proton bunch, an edge resolution of 0.6mm and hence an SMI saturation point resolution of 1.2m can be achieved.
CERN has launched a study phase to evaluate the feasibility of a new high-intensity beam dump facility at the CERN Super Proton Synchrotron accelerator with the primary goal of exploring Hidden ...Sector models and searching for Light Dark Matter, but which also offers opportunities for other fixed target flavour physics programs such as rare tau lepton decays and tau neutrino studies. The new facility will require—among other infrastructure—a target complex in which a dense target/dump will be installed, capable of absorbing the entire energy of the beam extracted from the SPS accelerator. In theory, the target/dump could produce very weakly interacting particles, to be investigated by a suite of particle detectors to be located downstream of the target complex. As part of the study, a development design of the target complex has been produced, taking into account the handling and remote handling operations needed through the lifetime of the facility. Two different handling concepts have been studied and both resulting designs are presented.
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