A Medium Energy Beam Transport line 1(MEBT1) has been designed for Injector Scheme II of the China ADS project. To match the beam from RFQ to Superconducting(SC) Half Wave Resonator(HWR) sections with emittance preservation, the MEBT1 has been designed to be mechanically compact. Working at 162.5 MHz,the MEBT1 transports a 10 m A, 2.1 Me V proton beam using seven quadrupoles and two bunching cavities within2.7 meters. Three collimators are placed between every two adjacent quadrupoles to collimate the beam halo. Design and construction of the MEBT1 are presented in this paper.
The China Accelerator Driven Subcritical System(China-ADS) project, which is a strategic plan and aims to design and build an ADS demonstration facility, has been proposed and launched actively in China. Injector as one of the parallel injectors of China-ADS, and is prompted by the Institute of Modern Physics(IMP). In this paper, a new scheme with full period lattice structure for the SC section is proposed. In the new scheme, there are sixteen periods, with one superconducting solenoid and one superconducting cavity included in each period. All of the elements are contained in four cryomodules. The dreadful influence of the mismatch caused by period structural change can be avoided, and the beam quality is favorable. In addition, this new scheme has certain advantages in reducing the project's difficulty and construction risk. The details of the design and beam dynamic simulation for the full period lattice structure are given in this paper.
The ADS(accelerator driven subcritical system) project was proposed by the Chinese Academy of Sciences.The initial proton beams delivered from an electron cyclotron resonance ion source can be effectively accelerated by 162.5 MHz 4.2 m long room temperature radio-frequency-quadrupoles(RFQ) operating in CW mode.To test the feasibility of this physical design,a new Fortran code for RFQ beam dynamics study,which is space charge dominated,was developed.This program is based on Particle-In-Cell(PIC) technique in the time domain.Using the RFQ structure designed for the CADS project,the beam dynamics behavior is performed.The well-known simulation code TRACK is used for benchmarks.The results given by these two codes show good agreements.Numerical techniques as well as the results of beam dynamics studies are presented in this paper.
A superconducting focusing solenoid has been designed and developed for the China Accelerator Driven System(CADS).In order to meet the requirement of focusing strength and fringe field while minimizing the physical size of the solenoid,the novel optimizing design method based on a linear programming method was employed.In this report,the design of the solenoid including magnetic field optimization,mechanical design and quench protection will be introduced.The solenoid has been fabricated and tested.The testing results show that the central field reached8.4 T and the stray field was lower than 50 Gauss in the cavity zone.
