China
Africa
Explore chapters and articles related to this topic
Superconductors in Future Accelerators: Irradiation Problems
Published in David A. Cardwell, David C. Larbalestier, Aleksander I. Braginski, Handbook of Superconductivity, 2023
René Flükiger, Tiziana Spina, Francesco Cerutti, Amalia Ballarino, Luca Bottura
This problem has been solved by replacing the fluence ϕt by a new parameter, the displacement per atom or dpa. This parameter is calculated by a Monte Carlo simulation package for the interaction and transport of particles and nuclei in matter, called FLUKA (FLUktuierende KAskade), which is used at CERN for estimating the radiation damage induced by high energy on materials, as discussed by Fassò et al. (2011), Cerutti et al. (2011) and Lechner et al. (2014) and more recently by Besana et al. (2017). The parameter dpa is correlated to the total number of individual Frenkel defects and is used by nuclear engineers for calculating the mechanical properties of steel after heavy irradiation. In contrast to the fluence ϕt, the total value of dpa can be obtained by a simple addition of its values for each one of the high energy particles. A quantitative consideration of the expected radiation effects on the superconductors in accelerators has been performed during the last years by Spina et al. (2015, 2016, 2017) and Flükiger et al. (2017, 2018).
Overview on Monte Carlo modelling
Published in Gavin Poludniowski, Artur Omar, Pedro Andreo, Calculating X-ray Tube Spectra, 2022
Gavin Poludniowski, Artur Omar, Pedro Andreo
FLUKA (FLUktuierende KAskade) is a Monte Carlo computer code system developed in the 1960s at the European Organization for Nuclear Research (CERN) for calculating the shielding of high-energy proton accelerators. The current version is the third generation system developed since 1989 with the support of Istituto Nazionale di Fisica Nucleare (INFN). FLUKA has over the years evolved into a powerful multipurpose tool that can simulate the transport of about 60 different particle types over broad ranges of energy. A useful recent addition is the front-end interface FLAIR [177], which facilitates editing of input files, executing simulations, and visualizing the output.
Generation of Bremsstrahlung Radiation from Different Low- to High-Z Targets for Medical Applications: A Simulation Approach
Published in Pandit B. Vidyasagar, Sagar S. Jagtap, Omprakash Yemul, Radiation in Medicine and Biology, 2017
Bhushankumar Jagnnath Patil, Vasant Nagesh Bhoraskar, Sanjay Daga Dhole
The radiation field of electron accelerator includes several components such as bremsstrahlung photons, fast neutrons, positrons, hadrons, and muons. The production and transport of all these radiations through different targets are difficult to study theoretically even on the basis of correct experiments. Therefore, simulations with an effective Monte Carlo code are very helpful to get information of all the particles produced in accelerator head and their dose deposition in patient’s body. A general purpose Monte Carlo based code FLUKA [27] has been used for the calculations of particle transport and interactions with matter. FLUKA code version 2006 and 2008 has been used to calculate the results. It can simulate of about 60 different particles with high accuracy, including photons, electrons, neutrons, heavy ions, and antiparticles. The lowest transport limit for all particles is ~1 keV. There are various tools for input geometry visualization and output plotting in two and three dimensions giving a clear picture of the calculations. FLUKA can handle very complex geometries, using an improved version of the well-known combinatorial geometry (CG) package. FLUKA uses an original transport algorithm for charged particles, including complete multiple Coulomb scattering treatment. It also uses Bethe–Bloch theory for energy loss mechanism. Delta-ray production via Bhabha and Moller scattering is implemented in FLUKA. In FLUKA the full set of Seltzer and Berger cross sections [28] of accurate electron-nucleus and electron-electron bremsstrahlung has been tabulated in an extended form [29]. FLUKA scores fluence and current as a function of energy and angle. It can also score track-length fluence in a binning structure (Cartesian or cylindrical) independent of geometry.
Radiation Protection at Petawatt Laser-Driven Accelerator Facilities: The ELI Beamlines Case
Published in Nuclear Science and Engineering, 2023
Anna Cimmino, Veronika Olšovcová, Roberto Versaci, Dávid Horváth, Benoit Lefebvre, Andrea Tsinganis, Vojtěch Stránský, Roman Truneček, Zuzana Trunečková
FLUKA is used for studies of induced radioactivity and nuclide production, nuclide decay, and transport of residual radiation. In fact, the results of these simulations allow for effective planning of maintenance/upgrade interventions in radiation-controlled environments, optimization of the materials used, and management of storage, treatment, and disposal of radioactive waste. The experimental teams and engineers are provided with general guidelines on the choice of materials, based both on the activation cross sections and FLUKA studies.57 Preferably, only materials with low radiological impact should be employed. However, since this is not always feasible, dedicated simulations for specific devices and geometry setups and representative irradiation history have been modeled. In some cases, additional moveable local shielding was designed to enable safe work in the vicinity of hot spots.
Production of High-Purity 52g Mn from nat V Targets with Alpha Beams at Cyclotrons
Published in Nuclear Technology, 2022
A. Colombi, M. P. Carante, F. Barbaro, L. Canton, A. Fontana
Fluka (development version 2018.2) is a general-purpose code for modeling particle transport and interaction with matter. It covers an extended range of applications, spanning from proton and electron accelerator shielding to calorimetry, dosimetry, detector design, radiotherapy, and more.23,27,28 The code, based on the PreEquilibrium Approach to NUclear Thermalization (PEANUT) module, can be used to calculate the production of residual nuclei, and in many cases, results have already been validated with experimental data. Residual nuclei (and, thus, radionuclides) emerge directly from the inelastic hadronic interaction models and can be calculated for arbitrary projectile-target configurations (including nucleus-nucleus interactions) and energies. Regarding the production of isomers, the Fluka version used in this work does not have a built-in routine to predict the correct branching for the production of different states of the same radionuclide, but it distributes the cross section equally over the different states. For this reason, we consider only the results of Fluka in the cases where the separation between ground and metastable nuclides is not explicitly involved.
Shield Design of the First Protective Collimator in the METU-Defocusing Beamline (DBL) Project
Published in Nuclear Technology, 2022
Selcen Uzun Duran, Pelin Uslu Kiçeci, Bilge Demirköz
The METU-DBL beam elements were defined in FLUKA for the simulation studies. FLUKA is a Monte Carlo code that is used in many applications, such as medical physics and radiobiology, to calculate the absorbed radiation dose and radiation cooling time. It provides accurate results in shielding designs, particularly in complicated three-dimensional geometries.5 FLUKA has different physics models for the different energy ranges in hadronic interactions. The PEANUT model has proved to be an accurate and reliable tool for intermediate energy hadron-nucleus interactions.6 During the simulations of the METU-DBL, it was determined that mostly gamma rays, electrons, and neutrons emerged as secondary particles. Since these secondary particles increase the dose levels in the R&D room, shielding the beam elements that intensely emit the secondary particles was necessary in order to reduce the radiation dose in the R&D room. Collimators were used to decrease the proton flux at the end, so the protons mostly hit these collimators, which resulted in a high dose around them. The shielding studies were started with the first protective collimator because the pretest design of the METU-DBL only has the first protective collimator. Therefore, this collimator was shielded to reduce the dose in the R&D room, especially for the safety of the radiation workers.