加速器物理
Longitudinal collective modes of a bunched beam with a repulsive inductive impedance (the space charge below transition or the chamber inductance above it) are analytically described by means of reduction of the linearized Vlasov equation…
FEbeam is a compact field emission data processing interface with the capability to analyze the field emission cathode performance in an rf injector by extracting the field enhancement factor, local field, and effective emission area from…
Particle accelerators require constant tuning during operation to meet beam quality, total charge and particle energy requirements for use in a wide variety of physics, chemistry and biology experiments. Maximizing the performance of an…
The mode coupling instability for coasting beams has been discussed in a previous paper using macroparticle tracking simulations from the pyHeadTail code and a simple analytical formula which was proposed as an extension of the ansatz used…
Fine time-resolved analysis of matter - i.e. spectroscopy and photon scattering - in the linear response regime requires a fs-scale pulsed, high repetition rate, fully coherent X-ray source. A seeded Free-Electron Laser (FEL) driven by a…
We present measurements of slice energy spread at the injector section of the European X-Ray Free Electron Laser for an electron bunch with charge of 250 pC. Two methods considered in the paper are based on measurements at the dispersive…
Since the introduction of the radio-frequency (rf) photoinjector electron source over thirty years ago, peak performance demands have dictated the use of high accelerating electric fields. With recent strong advances in obtainable field…
Dielectric disk accelerating (DDA) structures are being studied as an alternative to conventional disk-loaded copper structures. This paper investigates numerically an efficient X-band DDA structure operating at a higher order mode of…
The ORBIT code has been widely used for beam dynamics simulations including injection and acceleration in high-intensity hadron synchrotrons. When the ORBIT's 1D longitudinal tracking was employed for the acceleration process in CSNS/RCS,…
In this paper, we use an envelope equation-based approach to obtain analytical scaling laws for the shortest pulse length achievable using radiofrequency (RF) based bunch compression. The derived formulas elucidate the dependencies on the…
We present quantitative means for assessing the numerical accuracy of static magnetic field calculations in finite-element models. Our calculations use the three-dimensional Opera simulation software suite of Dassault Syst`emes. Our need to…
During the preparatory phase of the International Linear Collider (ILC) project, all technical development and engineering design needed for the start of ILC construction must be completed, in parallel with intergovernmental discussion of…
In the future the International Linear Collider (ILC), a helical undulator-based polarized positron source, is expected to be chosen. A high energy electron beam passes through a superconducting helical undulator in order to create…
Particle beam eigen-emittances comprise the lowest set of rms-emittances that can be imposed to a beam through symplectic optical elements. For cases of practical relevance this paper introduces an approximation providing a very simple and…
Blocks-in-Conduit is a novel approach to cable, coil, and splice technologies with unique benefits for a high-current-den-sity toroid D winding to operate at 20 T, 20 K. Blocks of REBCO tape are cabled in conduit, with a thin-wall…
High-repetition-rate sources of bright electron bunches have a wide range of applications. They can directly be employed as probes in electron-scattering setups, or serve as a backbone for the generation of radiation over a broad range of…
Since 2006, there have been unexpected trigger-failure events during the operation of the Japan Proton Accelerator Research Complex (J-PARC) timing system. However, among the many suspected modules, it has been difficult to find the one…
A superconducting linear accelerator operating in continuous-wave mode could produce X-ray free electron lasers (XFEL) at megahertz repetition rate, with the capability that delivering wide spectral range coherent radiation to multi end…
In recent years, a new generation of storage ring based light sources, known as diffraction limited storage rings (DLSRs), whose emittance approaches the diffraction limit for the range of X ray wavelengths of interest to the scientific…
To realise a planned high-luminosity and high-energy $e^+e^-$-collider, as the ILC, a large amount of positrons have to be produced and the accelerated particles have to be captured and matched according to the damping ring acceptances.…