{"title":"Design and test of an X-band constant gradient structure","authors":"Qiang Gao, Hao Zha, Jiaru Shi, Xiancai Lin, Yingchao Du, Boyuan Feng, Hongyu Li, Heng Deng, Fangjun Hu, Jian Gao, Qingzhu Li, Weihang Gu, Jiayang Liu, Wenhui Huang, Chuanxiang Tang, Huaibi Chen","doi":"10.1103/physrevaccelbeams.27.090401","DOIUrl":null,"url":null,"abstract":"A light source project named very compact inverse Compton scattering gamma-ray source (VIGAS) is under development at Tsinghua University. VIGAS aims to generate monochromatic high-energy gamma rays by colliding 350-MeV electron beams with 400-nm laser photons within a 12-m beamline. To produce a high-energy electron beam in such a compact space, the system consists of an S-band high-brightness injector and six X-band high-gradient accelerating structures. The goal of the X-band structure is to operate at a high gradient of <math display=\"inline\" xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mn>80</mn><mtext> </mtext><mtext> </mtext><mi>MV</mi><mo>/</mo><mi mathvariant=\"normal\">m</mi></mrow></math>. Therefore, we adopts the constant gradient traveling wave approach, where the iris from the first cell to the end cell is tapered. The structure has 72 cells, including 70 cells and 2 couplers, so we named it XT72. The frequency of XT72 is selected to 11.424 GHz, and the <math display=\"inline\" xmlns=\"http://www.w3.org/1998/Math/MathML\"><mn>2</mn><mi>π</mi><mo>/</mo><mn>3</mn></math> mode is adopted. In this paper, we present a comprehensive study covering the detailed design, fabrication, rf tuning, and high-power test results of the first XT72. Additionally, we compare the performance of this structure to that of the previous constant impedance structure. Our results demonstrate that the XT72 is capable of operating at an <math display=\"inline\" xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mn>80</mn><mtext>−</mtext><mrow><mi>MV</mi><mo>/</mo><mi mathvariant=\"normal\">m</mi></mrow></mrow></math> gradient with a lower breakdown rate. This advancement paves the way for the development of VIGAS project and contributes to the wider application of X-band room-temperature high-gradient structures in compact accelerator facilities.","PeriodicalId":54297,"journal":{"name":"Physical Review Accelerators and Beams","volume":null,"pages":null},"PeriodicalIF":1.5000,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Physical Review Accelerators and Beams","FirstCategoryId":"101","ListUrlMain":"https://doi.org/10.1103/physrevaccelbeams.27.090401","RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"PHYSICS, NUCLEAR","Score":null,"Total":0}
引用次数: 0
Abstract
A light source project named very compact inverse Compton scattering gamma-ray source (VIGAS) is under development at Tsinghua University. VIGAS aims to generate monochromatic high-energy gamma rays by colliding 350-MeV electron beams with 400-nm laser photons within a 12-m beamline. To produce a high-energy electron beam in such a compact space, the system consists of an S-band high-brightness injector and six X-band high-gradient accelerating structures. The goal of the X-band structure is to operate at a high gradient of . Therefore, we adopts the constant gradient traveling wave approach, where the iris from the first cell to the end cell is tapered. The structure has 72 cells, including 70 cells and 2 couplers, so we named it XT72. The frequency of XT72 is selected to 11.424 GHz, and the mode is adopted. In this paper, we present a comprehensive study covering the detailed design, fabrication, rf tuning, and high-power test results of the first XT72. Additionally, we compare the performance of this structure to that of the previous constant impedance structure. Our results demonstrate that the XT72 is capable of operating at an gradient with a lower breakdown rate. This advancement paves the way for the development of VIGAS project and contributes to the wider application of X-band room-temperature high-gradient structures in compact accelerator facilities.
期刊介绍:
Physical Review Special Topics - Accelerators and Beams (PRST-AB) is a peer-reviewed, purely electronic journal, distributed without charge to readers and funded by sponsors from national and international laboratories and other partners. The articles are published by the American Physical Society under the terms of the Creative Commons Attribution 3.0 License.
It covers the full range of accelerator science and technology; subsystem and component technologies; beam dynamics; accelerator applications; and design, operation, and improvement of accelerators used in science and industry. This includes accelerators for high-energy and nuclear physics, synchrotron-radiation production, spallation neutron sources, medical therapy, and intense-beam applications.