IMP hosts the project of high intensity Heavy Ion Accelerator Facility (HIAF). High power input couplers are needed for the SRF cavities. In order to assemble cryo-module easily and run the machine safely, new TTF-III...IMP hosts the project of high intensity Heavy Ion Accelerator Facility (HIAF). High power input couplers are needed for the SRF cavities. In order to assemble cryo-module easily and run the machine safely, new TTF-III like demountable dual-ceramic coupler is developed. This paper will present some results of the 162.5 MHz coupler for the tapper HWR cavity.展开更多
The reactive oxygen plasma cleaning was proved an efficient method to decrease the field emission effect of the HWR superconducting cavities on the vertical test platform.
Multicell superconducting radio frequency(SRF)elliptical cavities are proposed for efficient acceleration of proton beam in the Chinese initiative Accelerator Driven Subcritical System(CiADS).
The main goal of the Chinese ADS front-end demo superconducting linac(CAFe)is to develop the key technologies of a superconducting front-end linac and demonstrate high power continuous-wave(CW)proton beam with 10 mA f...The main goal of the Chinese ADS front-end demo superconducting linac(CAFe)is to develop the key technologies of a superconducting front-end linac and demonstrate high power continuous-wave(CW)proton beam with 10 mA for Accelerator Driven System(ADS).展开更多
The main goal of the Chinese ADS front-end demo superconducting linac(CAFe)is to develop the key technologies of a superconducting front-end linac and demonstrate high power continuous-wave(CW)proton beam with 10 mA f...The main goal of the Chinese ADS front-end demo superconducting linac(CAFe)is to develop the key technologies of a superconducting front-end linac and demonstrate high power continuous-wave(CW)proton beam with 10 mA for Accelerator Driven System(ADS).One of the crucial challenges is the reliability and availability of the accelerator.By the end of 2017,a CW beam commissioning test around 27 h was made.The majority of beam trips is from the SRF system in the test.Therefore,our intense effort was to improve the reliability of the SRF system in 2018,which are described below.展开更多
The 162.5 MHz HWR010 and HWR015 superconducting cavities have been used in the Chinese ADS 25 MeV demo SRF Linac.Each cavity is feed with RF power by one high power coupler.The maximum design coupler power is 20 kW in...The 162.5 MHz HWR010 and HWR015 superconducting cavities have been used in the Chinese ADS 25 MeV demo SRF Linac.Each cavity is feed with RF power by one high power coupler.The maximum design coupler power is 20 kW in traveling mode.Prior to assembly,couplers need to be tested and conditioned at room temperature.And the characteristics of conditioning phenomenon can also be thoroughly studied during the conditioning process.Figure 1 presents the block diagram of the test stand system.However,the previous test system is ineligible because of its sundry problems lying in its LLRF control system and its test stand.To overcome the defects of the previous test system,a series of improvements were performed.展开更多
The pilot ADS project hosted by IMP and IHEP,which aims to produce a CW proton beam with beam current 10 mA@25 MeV,has successfully ejected out a pulsed proton beam with beam current 12.6 mA@26.1 MeV.It has four cryom...The pilot ADS project hosted by IMP and IHEP,which aims to produce a CW proton beam with beam current 10 mA@25 MeV,has successfully ejected out a pulsed proton beam with beam current 12.6 mA@26.1 MeV.It has four cryomodules,totally 22 superconducting cavities.The first two cryomodules,each consists of six Half Wave Resonators(HWRs)with=0.1,have the same structure.The third cryomodule is made up of five tapered HWRs with=0.15.The first three cryomodules are supplied by IMP and the fourth one by IHEP,which consists of five elliptical cavities with=0.21.This paper will show some interesting results about cavity string assembling in cleanroom and the onset of field emission.展开更多
Field emission occurred in superconducting radio-frequency(SRF)cavities is the major obstacle of the accelerators operating at high gradient,which partly caused by the inner surface contamination,such as the hydrocarb...Field emission occurred in superconducting radio-frequency(SRF)cavities is the major obstacle of the accelerators operating at high gradient,which partly caused by the inner surface contamination,such as the hydrocarbons and the absorbed residual gas.The plasma processing can be an effective method to solve the field emission issues.The properties of low temperature glow discharge,which was argon plasma with the chemically reactive oxygen,were investigated for the SRF cavities used for CADS project.展开更多
The high power superconducting radiofrequency(SRF)input coupler is the connecting part between the SRF cavity and the RF transmission line.With the RF power transferred through the coupler,the SRF cavity can built up ...The high power superconducting radiofrequency(SRF)input coupler is the connecting part between the SRF cavity and the RF transmission line.With the RF power transferred through the coupler,the SRF cavity can built up the electromagnetic field and then accelerate the beams.In addition to this RF transmission function,it also has to serve as a vacuum barrier for the SRF cavity vacuum.The HWR010 coupler which designed by IHEP is a single ceramic window coupler.展开更多
Room-temperature test with high power is an essential step before couplers are installed on superconducting cavities.A new room-temperature test stand is being designed at IMP.The new stand will be assembled with a NC...Room-temperature test with high power is an essential step before couplers are installed on superconducting cavities.A new room-temperature test stand is being designed at IMP.The new stand will be assembled with a NC(normal-conducting)QWR cavity.The power loss on the cavity when couplers are conditioned in traveling-wave mode has to be thoroughly evaluated.Fig.1 demonstrates the power flow in traveling-wave conditioning mode.Pe1 and Pe2 represent the power that is extracted by couplers.Pf and Pre denote the forward power and reflected power,respectively.展开更多
Spoke cavities have been developed and have apparent advantages for high current proton accelerator based on Fig.1(color online)The electromagnetic field distribution.superconductivity at low and medium energy region....Spoke cavities have been developed and have apparent advantages for high current proton accelerator based on Fig.1(color online)The electromagnetic field distribution.superconductivity at low and medium energy region.As the research and the technical reserve,Institute of Modern Physics(IMP)has started the R&D program of a double spoke cavity(operating frequency 325 MHz, 0=0.52),within the framework of China Accelerator Driven System(C-ADS)project.The RF design and mechanical structure design have been finished,and two prototype cavities were manufactured in Harbin.展开更多
There are two types of HWR cavities have been developed in IMP for C-ADS Injector.HWR010s have been used to accelerate proton from 2.1 MeV to 10 MeV.There are 12 HWR010s assembled in two CMs.The taper type HWR015s hav...There are two types of HWR cavities have been developed in IMP for C-ADS Injector.HWR010s have been used to accelerate proton from 2.1 MeV to 10 MeV.There are 12 HWR010s assembled in two CMs.The taper type HWR015s have been used to accelerate proton from 10MeV to 18.5 MeV.There are 5 HWRs assembled in the third CM.Proton beam has been accelerated to 26 MeV by HWR010,HWR015 and Spoke021 in June 2017.The beam has been accelerated to 18.5 MeV by HWR010 and HWR015.The CMs in the tunnel are shown in Fig.1.展开更多
功率耦合器是粒子加速腔射频功率馈送的关键部件。耦合器在安装至加速腔之前,必须进行常温高功率测试和锻炼,以检验加工工艺和设计指标,提高其射频性能。详细介绍了中国科学院近代物理研究所ADS25 Me V加速器样机162.5 MHz耦合器测试平...功率耦合器是粒子加速腔射频功率馈送的关键部件。耦合器在安装至加速腔之前,必须进行常温高功率测试和锻炼,以检验加工工艺和设计指标,提高其射频性能。详细介绍了中国科学院近代物理研究所ADS25 Me V加速器样机162.5 MHz耦合器测试平台的改进设计。针对原有接触式测试锻炼方式的不足,提出非接触式测试锻炼方案。对耦合器测试锻炼过程进行了物理抽象,采用理论模拟的方法分析测试腔体功率传输。基于分析结果设计了低损耗、宽通带、多用途的非接触式耦合器测试腔体。该腔体可实现20 k W测试功率下60 W左右的腔体损耗和15 MHz-3 d B带宽。展开更多
文摘IMP hosts the project of high intensity Heavy Ion Accelerator Facility (HIAF). High power input couplers are needed for the SRF cavities. In order to assemble cryo-module easily and run the machine safely, new TTF-III like demountable dual-ceramic coupler is developed. This paper will present some results of the 162.5 MHz coupler for the tapper HWR cavity.
文摘The reactive oxygen plasma cleaning was proved an efficient method to decrease the field emission effect of the HWR superconducting cavities on the vertical test platform.
文摘Multicell superconducting radio frequency(SRF)elliptical cavities are proposed for efficient acceleration of proton beam in the Chinese initiative Accelerator Driven Subcritical System(CiADS).
文摘The main goal of the Chinese ADS front-end demo superconducting linac(CAFe)is to develop the key technologies of a superconducting front-end linac and demonstrate high power continuous-wave(CW)proton beam with 10 mA for Accelerator Driven System(ADS).
文摘The main goal of the Chinese ADS front-end demo superconducting linac(CAFe)is to develop the key technologies of a superconducting front-end linac and demonstrate high power continuous-wave(CW)proton beam with 10 mA for Accelerator Driven System(ADS).One of the crucial challenges is the reliability and availability of the accelerator.By the end of 2017,a CW beam commissioning test around 27 h was made.The majority of beam trips is from the SRF system in the test.Therefore,our intense effort was to improve the reliability of the SRF system in 2018,which are described below.
文摘The 162.5 MHz HWR010 and HWR015 superconducting cavities have been used in the Chinese ADS 25 MeV demo SRF Linac.Each cavity is feed with RF power by one high power coupler.The maximum design coupler power is 20 kW in traveling mode.Prior to assembly,couplers need to be tested and conditioned at room temperature.And the characteristics of conditioning phenomenon can also be thoroughly studied during the conditioning process.Figure 1 presents the block diagram of the test stand system.However,the previous test system is ineligible because of its sundry problems lying in its LLRF control system and its test stand.To overcome the defects of the previous test system,a series of improvements were performed.
文摘The pilot ADS project hosted by IMP and IHEP,which aims to produce a CW proton beam with beam current 10 mA@25 MeV,has successfully ejected out a pulsed proton beam with beam current 12.6 mA@26.1 MeV.It has four cryomodules,totally 22 superconducting cavities.The first two cryomodules,each consists of six Half Wave Resonators(HWRs)with=0.1,have the same structure.The third cryomodule is made up of five tapered HWRs with=0.15.The first three cryomodules are supplied by IMP and the fourth one by IHEP,which consists of five elliptical cavities with=0.21.This paper will show some interesting results about cavity string assembling in cleanroom and the onset of field emission.
文摘Field emission occurred in superconducting radio-frequency(SRF)cavities is the major obstacle of the accelerators operating at high gradient,which partly caused by the inner surface contamination,such as the hydrocarbons and the absorbed residual gas.The plasma processing can be an effective method to solve the field emission issues.The properties of low temperature glow discharge,which was argon plasma with the chemically reactive oxygen,were investigated for the SRF cavities used for CADS project.
文摘The high power superconducting radiofrequency(SRF)input coupler is the connecting part between the SRF cavity and the RF transmission line.With the RF power transferred through the coupler,the SRF cavity can built up the electromagnetic field and then accelerate the beams.In addition to this RF transmission function,it also has to serve as a vacuum barrier for the SRF cavity vacuum.The HWR010 coupler which designed by IHEP is a single ceramic window coupler.
文摘Room-temperature test with high power is an essential step before couplers are installed on superconducting cavities.A new room-temperature test stand is being designed at IMP.The new stand will be assembled with a NC(normal-conducting)QWR cavity.The power loss on the cavity when couplers are conditioned in traveling-wave mode has to be thoroughly evaluated.Fig.1 demonstrates the power flow in traveling-wave conditioning mode.Pe1 and Pe2 represent the power that is extracted by couplers.Pf and Pre denote the forward power and reflected power,respectively.
文摘Spoke cavities have been developed and have apparent advantages for high current proton accelerator based on Fig.1(color online)The electromagnetic field distribution.superconductivity at low and medium energy region.As the research and the technical reserve,Institute of Modern Physics(IMP)has started the R&D program of a double spoke cavity(operating frequency 325 MHz, 0=0.52),within the framework of China Accelerator Driven System(C-ADS)project.The RF design and mechanical structure design have been finished,and two prototype cavities were manufactured in Harbin.
文摘There are two types of HWR cavities have been developed in IMP for C-ADS Injector.HWR010s have been used to accelerate proton from 2.1 MeV to 10 MeV.There are 12 HWR010s assembled in two CMs.The taper type HWR015s have been used to accelerate proton from 10MeV to 18.5 MeV.There are 5 HWRs assembled in the third CM.Proton beam has been accelerated to 26 MeV by HWR010,HWR015 and Spoke021 in June 2017.The beam has been accelerated to 18.5 MeV by HWR010 and HWR015.The CMs in the tunnel are shown in Fig.1.
文摘功率耦合器是粒子加速腔射频功率馈送的关键部件。耦合器在安装至加速腔之前,必须进行常温高功率测试和锻炼,以检验加工工艺和设计指标,提高其射频性能。详细介绍了中国科学院近代物理研究所ADS25 Me V加速器样机162.5 MHz耦合器测试平台的改进设计。针对原有接触式测试锻炼方式的不足,提出非接触式测试锻炼方案。对耦合器测试锻炼过程进行了物理抽象,采用理论模拟的方法分析测试腔体功率传输。基于分析结果设计了低损耗、宽通带、多用途的非接触式耦合器测试腔体。该腔体可实现20 k W测试功率下60 W左右的腔体损耗和15 MHz-3 d B带宽。
