High Energy Physics has been consistently pushing the performance of technical superconductors, for the benefit of high field magnet technology. So far the workhorse for particle accelerators has ...been Nb-Ti, but the practical performance limit has been attained with the LHC. Calls for higher beam luminosity (e.g., HL-LHC), and higher beam energy (e.g., FCC), demand a transition from Nb-Ti to Nb 3 Sn, presently the only practical candidate material offering the required high field performance. This paper provides a summary of desirable properties and performance targets for Nb 3 Sn to satisfy the challenging magnet specifications for upgrades of existing and future HEP accelerators.
Modeling techniques and tailored computational tools are becoming increasingly relevant to the design and analysis of large-scale superconducting magnet systems. Efficient and reliable tools are ...useful to provide an optimal forecast of the envelope of operating conditions and margins, which are difficult to test even when a prototype is available. This knowledge can be used to considerably reduce the design margins of the system, and thus the overall cost, or increase reliability during operation. An integrated analysis of a superconducting magnet system is, however, a complex matter, governed by very diverse physics. This paper reviews the wide spectrum of phenomena and provides an estimate of the time scales of thermal, hydraulic, and electromagnetic mechanisms affecting the performance of superconducting magnet systems. The analysis is useful to provide guidelines on how to divide the complex problem into building blocks that can be integrated in a design and analysis framework for a consistent multiphysics simulation.
GaToroid: A novel toroidal gantry for hadron therapy Bottura, L.; Felcini, E.; De Rijk, G. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
12/2020, Letnik:
983
Journal Article
Recenzirano
Odprti dostop
We describe here a novel concept of a gantry for hadron therapy, based on the use of a toroidal field configuration. The main features of this concept are that the gantry is not rotating, and is ...operated in steady-state We propose that is built based on superconducting magnets, reaching field levels not achievable using normal conducting iron-dominated magnets. The simplification resulting from the specific magnetic configuration, and the scale reduction that can be achieved using high-field superconducting magnets, bear a definite potential for significant reduction of dimensions and mass. In this paper we introduce the concept of the toroidal gantry, discussing the features of beam transport in a toroidal field. We then provide general considerations on the design of the coil, and analytical scaling of relevant indicators such as forces and stored energy. Finally, we give an example of practical layouts for a proton gantry that can be used as a benchmark for comparison with other designs.
Advanced Accelerator Magnets for Upgrading the LHC Bottura, L.; de Rijk, G.; Rossi, L. ...
IEEE transactions on applied superconductivity,
06/2012, Letnik:
22, Številka:
3
Journal Article, Conference Proceeding
Recenzirano
Odprti dostop
The Large Hadron Collider is working at about half its design value, limited by the defective splices of the magnet interconnections. While the full energy will be attained after the splice ...consolidation in 2014, CERN is preparing a plan for a Luminosity upgrade (High Luminosity LHC) around 2020 and has launched a pre-study for exploring an Energy upgrade (High Energy LHC) around 2030. Both upgrades strongly rely on advanced accelerator magnet technology, requiring dipoles and quadrupoles of accelerator quality and operating fields in the 11-13 T range for the luminosity upgrade and 16-20 T range for the energy upgrade. The paper will review the last ten year of Nb 3 Sn accelerator magnet R&D and compare it to the needs of the upgrades and will critically assess the results of the Nb 3 Sn and HTS technology and the planned R&D programs also based on the inputs of first year of LHC operation.
Abstract
This paper analyses the application of a two harmonics circuit with additional active filter for the powering of the four RCS stages of the muon acceleration to the ultimate 10 TeV energy ...level.
Known expressions, for the critical temperature, critical field and pinning force in NbTi are combined into a self-consistent fit formula that provides the critical current density as a function of ...temperature and field. The main advantage of such a fit is the extended validity range. Data available in literature and measurements on LHC strands are used to demonstrate the accuracy of the fit. The J/sub c/ data-sets used to cover a range of field from 0 T to 9 T and temperature from 1.9 K to 9 K. The standard deviation of the fits presented is of the order of 5% or better. This accuracy is generally sufficient for design purposes, extrapolation and scaling of measured results. Better accuracy, e.g. for short sample limit prediction, can be achieved restricting the domain of validity.
•The latest numerical issue is solved in the quench model of superconducting magnets.•A general pitfall in the linearized scheme is discussed as a target of iterative step control.•A novel idea of ...non-iterative control is introduced regarding the upcoming event.•A practical analysis is carried out for the usage of applied superconductivity in large-scale.
As an important issue of the quench simulation in large-scale applications, the effect of time step control is discussed on the well-known thermo-hydraulic model of superconducting magnets. Through our approach of model reduction, the reason of numerical anomaly is identified in terms of the time stepping around dynamical events, and just leads an effective countermeasure against the observed issue. Apart from the practical means out of such an investigation, a novel idea of non-iterative time step adaptation is introduced as a breakthrough not only being applied to the quench propagation model itself, but also to be extended to the common pitfalls of linearization scheme in general transient PDE (partial differential equation) problems.
Abstract
GaToroid, a novel gantry configuration for hadron therapy, is based on superconducting coils that generate a toroidal magnetic field to deliver the beam to the tumour location. Designing the ...complex GaToroid coils requires careful consideration of the local beam optical effects. We present a Python-based tool for charged particle transport in complex electromagnetic fields. The code implements fast tracking in arbitrary three-dimensional field maps, and it does not require a definition of specific or regular reference trajectories, as is generally the case for accelerator physics codes. The tool was used to characterise the beam behaviour inside the GaToroid system: to automatically determine the reference trajectories in the symmetry plane and analyse three-dimensional beam dynamics around these trajectories. Beam optical parameters in the field region were compared for various magnetic configurations of GaToroid. This paper introduces the new tracker and shows the benchmarking results. Furthermore, first-order beam optics studies for different arrangements demonstrate the main code features and serve for the design optimisation.
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