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The Monte Carlo toolkit Geant4 is used to simulate the production of a number of positron emitting radionuclides: 13 N, 18 F, 44 Sc, 52 Mn, 55 Co 61 Cu, 68 Ga, 86 Y, 89 Zr and 94 Tc, which have been produced using a 13 MeV medical cyclotron. The results are compared to previous simulations with the Monte Carlo code FLUKA and experimental measurements. The comparison shows variable degrees of agreement for different isotopes. The mean absolute deviation of Monte Carlo results from experiments was 1.4 ± 1.6 for FLUKA and 0.7 ± 0.5 for Geant4 using TENDL cross sections with QGSP-BIC-AllHP physics. Both agree well within the large error, which is due to the uncertainties present in both experimentally determined and theoretical reaction cross sections. Overall, Geant4 has been confirmed as a tool to simulate radionuclide production at low proton energy. [ABSTRACT FROM AUTHOR]

A proton therapy project HUST-PTF (HUST Proton Therapy Facility) based on a 250 MeV isochronous superconducting cyclotron is under development in Huazhong University of Science and Technology (HUST). In this paper we report the main design features of the beam line in HUST-PTF project. The energy selection system (ESS) for energy modulation is discussed in detail, including the collimators, momentum slit and transmission calculation. Due to significant difference among the transmissions of ESS for different energies, the intensity suppression scheme by defocusing beam at high energies on collimators in the beam line is proposed and discussed. Finally, the ratios of beam intensities between low and high energies are expected to be controlled within 10 to meet the clinical requirement, and the beam optics of each energy step after intensity suppression is studied respectively. [ABSTRACT FROM AUTHOR]

In this work we investigate the effect of the bunch pattern in a linac on the Higher Order Mode (HOM) power generation. The future ERL-based electron–ion collider eRHIC at BNL is used as an illustrative example. This ERL has multiple high current Superconducting Radiofrequency (SRF) 5-cell cavities. The HOM power generated when a single bunch traverses the cavity is estimated by the corresponding loss factor. Multiple re-circulations through the Energy Recovery Linac (ERL) create a specific bunch pattern. In this case the loss factor can be different than the single bunch loss factor. HOM power can vary dramatically when the ERL bunch pattern changes. The HOM power generation can be surveyed in the time and frequency domains. We estimate the average HOM power in a 5-cell cavity with different ERL bunch patterns. [ABSTRACT FROM AUTHOR]

High-field superconducting accelerator magnets are a key technology of the future circular collider. In order to master the technical challenges and achieve the performance targets, CERN has launched a technology development program. The first step of the program is to explore the Nb3Sn performance limits at 18 T field level and high stress, simplifying to the maximum the coil geometry. The first magnet to be built, the enhanced racetrack model coil (ERMC), aims at a mid-plane field of 16 T with 10% margin on the load line at 4.2 K. The ERMC is composed of two flat racetrack coils with no bore. To further develop the block-coil geometry, a second magnet, the racetrack model magnet (RMM), will be composed of two ERMC coils and a middle coil with a 50-mm closed cavity, addressing the issue of the design of an inner support to compensate for the preload forces. The RMM aims at a central field of 16 T in a 50-mm cavity, with 10% margin at 4.2 K. The next step is to develop a more compact and cost-effective design using two cable sizes, and therefore two different current densities. The coils will be assembled in a shell-based support structure using bladders and keys, which allows a precise control of the stress with minimal spring back and conductor overstress. This paper describes the magnetic and mechanical design of the ERMC and the RMM. [ABSTRACT FROM PUBLISHER]

An X-band high gradient accelerating structure is a challenging technology for implementation in advanced electron linear accelerator facilities. The present work discusses the design of an X-band accelerating structure for dedicated application to a compact hard X-ray free electron laser facility at the Shanghai Institute of Applied Physics, and numerous design optimizations are conducted with consideration for radio frequency (RF) breakdown, RF efficiency, short-range wakefields, and dipole/quadrupole field modes, to ensure good beam quality and a high accelerating gradient. The designed X-band accelerating structure is a constant gradient structure with a 4π/5 operating mode and input and output dual-feed couplers in a racetrack shape. The design process employs a newly developed effective optimization procedure for optimization of the X-band accelerating structure. In addition, the specific design of couplers providing high beam quality by eliminating dipole field components and reducing quadrupole field components is discussed in detail. [ABSTRACT FROM AUTHOR]

After the invention of the cyclotron by Ernest Lawrence and Robert Wilson’s suggestion to use the Bragg peak in the depth-dose distribution of protons to apply a high radiation dose selectively into a tumor, the first patient was treated with energetic ions at the Bevatron in Berkeley in 1950. Since then cyclotrons and synchrotrons have been used to accelerate protons and ions for particle therapy. In the first 50 years of particle therapy many treatment facilities were located at laboratory based accelerators, but since 2000 the number of clinical facilities in a hospital based environment is increasing. An overview of developments in and related to the accelerators typically used in this medical application will be presented. This paper will concentrate on developments in cyclotrons and synchrotrons, since these two accelerator types are and are likely to remain the major accelerator types used for therapy in the coming years. [ABSTRACT FROM PUBLISHER]

Multivariate polynomial multiplication is a fundamental operation which is used in many scientific domains, for example in the optics code for particle accelerator design at CERN. We present a novel and efficient multivariate polynomial multiplication algorithm for GPUs using floating-point double precision coefficients implemented using the CUDA parallel programming platform. We obtain very good speedups over another multivariate polynomial multiplication library for GPUs (up to 548x), and over the implementation of our algorithm for multi-core machines using OpenMP (up to 7.46x). [ABSTRACT FROM AUTHOR]

Abstract: The new linac injector SSC-LINAC has been proposed to replace the existing Separator Sector Cyclotron (SSC). This effort is to improve the beam efficiency of the Heavy Ion Research Facility of Lanzhou (HIRFL). As a key component of the linac, a continuous-wave (CW) mode high charge state heavy ion radio-frequency quadrupole (RFQ) accelerator has been designed. It accelerates ions with the ratio of mass to charge up to 7 from 3.728keV/u to 143keV/u. The requirements of CW mode operation and the transportation of intense beam have been considered as the greatest challenges. The design is based on 238U34+ beams, whose current is 0.5pmA (0.5 particle mili-ampere, which is the measured 17 emA electric current divided by charge state of heavy ions). It achieves the transmission efficiency of 94% with 2508.46mm long vanes in simulation. To improve the transmission efficiency and quality of the beams, the phase advance has been taken into account to analyze the reasons of beam loss and emittance growth. Parametric resonance and beam mismatch have been carefully avoided by adjusting the structure parameters. The parameter-sensitivity of the design is checked by transportation simulations of various input beams. To verify the applicability of machining, the effects of different vane manufacturing methods on beam dynamics are presented in this paper. [Copyright &y& Elsevier]

The article describes the research leading to the discovery of evidence of the Higgs boson particle, focusing on the A Toroidal LHC Apparatus (ATLAS) and Compact Muon Solenoid (CMS) experiments at the Large Hadron Collider (LHC). Researchers looked for a heavy boson with a mass consistent with the standard model of particle physics. Topics include the design and construction of the LHC particle accelerator, experimental designs for the ATLAS and CMS Collaborations, and potential research into the existence of a scalar field and its role in dark energy and supersymmetry.

The article focuses on the construction of the second accelerator, the Taiwan Photon Source (TPS), at the National Synchrotron Radiation Research Center (NSRRC), which entered its third year of construction in 2012. It says that the TPS will be fitted with a low-emittance synchrotron storage ring and a three gigaelectronvolt (GeV) electron energy. It also mentions that the TPS is the solution to the problem of Taiwan regarding the long-term development of science and technology.

What is the ultimate limit to high fields in superconducting magnets for particle accelerators? In this paper we review the present status of the technology, outlining the main limitations. We first analyse the needed margin for operating a magnet in an accelerator. We then review the relation between current densities, coil widths, and fields in the magnets build so far. The issue of stress and the dependence on the coil lay-out is then discussed: a careful optimization between current density and coil width can be needed to keep the forces and associated strain within acceptable limits. The main issues related to cable lay-out (strand diameter, filament size) are then discussed. We conclude by giving a hint on the requirements on a HTS conductor, and a summary of Nb-Ti and Nb3Sn. [ABSTRACT FROM PUBLISHER]

The CERN PS Booster project foresees the injection of 160 MeV H^- ions into the booster from Linac 4. For this substantial upgrade, a system of 5 pulsed magnets (BIDIS) and 3 vertical septa (BISMV) will distribute the Linac pulses into the four-vertically separated Booster injection lines before being injected into the rings. This paper describes the magnetic calculations and the design concept that will be used in the future upgrade of the BISMV. Subsequently the mechanical design of the septa and their integration into the existing transfer line will be discussed. [ABSTRACT FROM PUBLISHER]

Superconducting linear accelerators include a superconducting magnet system for particle beam transportation that provides beam focusing and steering. This system consists of a large number of quadrupole magnets and dipole correctors mounted inside or between cryomodules with SCRF cavities. Each magnet has current leads and is powered from its own power supply. The paper proposes a novel approach to magnet powering based on using superconducting persistent current switches. A group of magnets is powered by the same power supply through the common, for the group of cryomodules, electrical bus, and pair of current leads. Superconducting switches direct the current to the chosen magnet and close the circuit, providing the magnet operation in a persistent current mode. Two persistent current switches were fabricated and tested. The paper also presents the results of magnetic field simulations, decay time constants analysis, and a way of improving quadrupole magnetic center stability. Such an approach substantially reduces the magnet system cost and increases the reliability. [ABSTRACT FROM PUBLISHER]

Abstract: The 6MeV LINAC based pulsed thermal neutron source has been designed for bulk materials analysis. The design was optimized by varying different parameters of the target and materials for each region using FLUKA code. The optimized design of thermal neutron source gives flux of with more than 80% of thermal neutrons and neutron to gamma ratio was . The results of prototype experiment and simulation are found to be in good agreement with each other. [Copyright &y& Elsevier]

Abstract: Based on a 10MeV CRM cyclotron developed at China Institute of Atomic Energy (CIAE) with an achieved beam intensity of up to 430μA, a 14MeV high intensity compact cyclotron, CYCIAE-14, was designed and being built at CIAE. It is planned that the first machine would be in place with a span of 2years. CYCIAE-14 is delicately designed to realize strong vertical focusing by adopting a 4-sector, variable hill-gap structure with an external ion source to achieve high intensity. A special design applied to the stripping extraction gives access to dual extraction with four beams. The adoption of sophisticated industrial technology will give the cyclotron advantages, e.g. low power consumption and high reliability. This paper is aimed to present the overall design of the machine, including the basic technical specifications, main magnet and coils, RF, ion source and axial injection, and stripping extraction, etc. It will also give an introduction to its construction schedule as well as the up-to-date progress. [Copyright &y& Elsevier]

Abstract: This paper introduces the physics design of a 70MeV high intensity cyclotron at China Institute of Atomic Energy (CIAE), which is aimed for multiple uses including radioactive ion-beam (RIB) production. The machine adopts a compact structure of four straight sectors, capable of accelerating two kinds of beams, i.e. H− and D− . The proton and deuteron beam will be extracted in dual opposite directions by charge exchange stripping devices. The energy of the extracted proton beam is in the range 35–70MeV with an intensity up to 700μA. The corresponding values for the deuteron beam are 18–33MeV and 40μA. This paper will present the main characteristics and parameters in the design of the 70MeV cyclotron, the results of the basic beam dynamics study, as well as the physics in the design of the different systems, including the main magnet, RF, injection and extraction systems, etc. [Copyright &y& Elsevier]

Abstract: This paper outlines the conceptual design work of a high power proton cyclotron proposed by the China Institute of Atomic Energy (CIAE) for a spallation neutron source, accelerator driven systems, production of radioactive ion beams, and other applications. For this cyclotron the 100MeV injection proton beam is currently considered to be provided by the CYCIAE-100 cyclotron, which is under construction at CIAE and will be later replaced by a dedicated injector for beam upgrading. In order to minimize beam losses for high intensity operation, large turn separation at the extraction has first priority. After analyzing of different scenarios, including super conducting designs, a warm magnet solution was chosen. The conceptual design, field calculations, RF cavity simulations, etc. will be presented in the paper. [Copyright &y& Elsevier]

Abstract: A 14MeV high intensity cyclotron CYCIAE-14 dedicated to Positron Emission Tomography (PET) is under construction at China Institute of Atomic Energy (CIAE). Based on a set of basic technical requirements for the accelerator and its extracted beam, the cyclotron beam dynamics were studied and the results are presented. Static beam dynamics, beam motion inside the machine under imperfection conditions and beam behavior in the extraction process were also investigated. This work gives an in-depth view of the beam dynamics study, numerical simulation as well as the corresponding results and necessary analyses. [Copyright &y& Elsevier]

Abstract: The cyclotron has an obvious advantage in offering high average current and beam power. Cyclotron development for various applications, e.g. radioactive ion-beam (RIB) generation, clean nuclear energy systems, medical diagnostics and isotope production, were performed at China Institute of Atomic Energy (CIAE) for over 50years. At the moment two cyclotrons are being built at CIAE, the 100MeV, CYCIAE-100, and a 14MeV, the CYCIAE-14. Meanwhile, we are designing and proposing to build a number of cyclotrons with different energies, among them are the CYCIAE-70, the CYCIAE-800, and the upgrading of CYCIAE-CRM, which is going to increase its beam current to mA level. The contribution will present an overall introduction to the cyclotron development activities conducted at CIAE, with different emphasis to each project in order to demonstrate the design and construction highlights. [Copyright &y& Elsevier]

Abstract: In order to improve the quality of deuteron-induced activation data required for the safety design of the IFMIF (International Fusion Materials Irradiation Facility), we have measured (1) the activation cross-section of natLi(d,x)7Be in the deuteron-energy range from 7 to 39MeV and (2) the production rates of radioactive nuclides in thick targets for natLi(d,x)7Be, natC(d,x)7Be, and 27Al(d,x)7Be, 22Na, 24Na reactions at 40MeV using the AVF cyclotron of Tohoku University. We have also estimated the production rates of these nuclides in the thick targets below 40MeV using the cross-sections obtained in this study. The present data compared favorably with other experimental data, IAEA-recommended data, and the data obtained using the recent nuclear reaction code TALYS and the activation code IRACM, which is based on the ALICE-F code. Some calculation results showed marked disagreement with the experimental data. [Copyright &y& Elsevier]

Abstract: The IFMIF-EVEDA accelerator will be a 9MeV, 125mAcw deuteron accelerator prototype for verifying the validity of the 40MeV accelerator design for IFMIF. A beam dump designed for maximum power of 1.12MW will be used to stop the beam at the accelerator exit. The conceptual design for the IFMIF-EVEDA accelerator beam dump is based on a conical beam stop made of OFE copper. The cooling system uses an axial high velocity flow of water pressurized up to 3.4×105 Pa to avoid boiling. The design has been shown to be compliant with ASME mechanical design rules under nominal full power conditions. A sensitivity analysis has been performed to take into account the possible margin on the beam properties at the beam dump entrance. This analysis together with the study of the maintenance issues and the mounting and dismounting operations has led to the complete design definition. [Copyright &y& Elsevier]

Abstract: This paper resumes the study of the development of high precision joints performed by vacuum brazing as part of the fabrication of accelerating structures and other parts of particle accelerators. The study is focused on the selection of the most suitable parameters for carrying out high quality copper/copper and copper/stainless steel joints such as thermal cycle, filler material, filler grooves design, surface preparation, thickness of Ni plating and joint clearance. The joint characterization was carried out by means of microstructural (OM, SEM) and compositional (EDS) techniques and by leaking test. [Copyright &y& Elsevier]

The constant field nature of a fixed field alternating gradient (FFAG) accelerator requires a modeling which separates the layout of accelerator elements from the geometry of beam orbits. A new code, named s-code, is made to design an FFAG accelerator and to track a beam in it. We will describe the model of accelerator elements and the way to integrate the equation of motion of a particle. [ABSTRACT FROM AUTHOR]