中国散裂中子源研发了一台射频四极RFQ(Radio Frequency Quadrupole)强流质子加速器。为保证RFQ顺利出束,对加工焊接阶段、RF调谐调场、高功率RF(Radio Frequency)老练过程中出现的问题进行了分析,给出了解决办法,并进行了调束实验。三...中国散裂中子源研发了一台射频四极RFQ(Radio Frequency Quadrupole)强流质子加速器。为保证RFQ顺利出束,对加工焊接阶段、RF调谐调场、高功率RF(Radio Frequency)老练过程中出现的问题进行了分析,给出了解决办法,并进行了调束实验。三坐标测量测得RFQ精加工后的加工公差约在20μm,RFQ腔体无载品质因子Q0大于7 679,约为理论无载Q0值的80%。RFQ腔内RF电场分布的平整度好于2.5%,RFQ高功率RF老练入腔功率达到450 k W,是理论腔耗390 k W的1.15倍,且保持连续12 h不打火。在RFQ调束实验中,RFQ出口得到3 Me V、28 m A的负氢束流,满足中国散裂中子源的要求。展开更多
SSC-Linac RFQ(Separated Sector Cyclotron Linac Radio Frequency Quadrupolec)是中国科学院近代物理研究所和北京大学共同研制的国内首台高电荷态强流重离子连续波四杆型加速器,机械加工的高精度是RFQ能否顺利出束的关键步骤之一。...SSC-Linac RFQ(Separated Sector Cyclotron Linac Radio Frequency Quadrupolec)是中国科学院近代物理研究所和北京大学共同研制的国内首台高电荷态强流重离子连续波四杆型加速器,机械加工的高精度是RFQ能否顺利出束的关键步骤之一。为了检测其机械形位公差,采用了激光跟踪仪和关节测量臂合理组合应用的测量新方法,使两种高精度的测量仪器能扬长避短,克服了大尺度工件形位公差传统测量方法的不足,使其在测量过程中发挥其最优的使用性和操作性,有效地提高了工作效率,从而保证RFQ高精度的测量结果。展开更多
射频四极场加速器(Radio Frequency Quadrupole,RFQ)广泛应用于质子加速器装置中,高频率、紧凑型RFQ的发展可以推动质子加速器装置的小型化,同时也面临调谐困难的问题。紧凑型RFQ的性能对腔体尺寸的敏感度高,基于理论物理特性的传统调...射频四极场加速器(Radio Frequency Quadrupole,RFQ)广泛应用于质子加速器装置中,高频率、紧凑型RFQ的发展可以推动质子加速器装置的小型化,同时也面临调谐困难的问题。紧凑型RFQ的性能对腔体尺寸的敏感度高,基于理论物理特性的传统调谐算法难以取得良好效果,而基于腔体实际物理特性的调谐算法则可以解决紧凑型RFQ的调谐难点。本文提出了一种基于响应矩阵和最小二乘法的调谐算法,该算法可以限定求解的范围,避免计算结果超出调谐器可调谐范围的问题;为二极场分量赋予权重,可以高效地降低二极场误差,解决二极场分量难以调谐的问题。根据新的调谐算法分别在模拟环境下的RFQ样机上完成了调谐实验,在搭建的测量平台获得的结果显示:初始状态下二、四极场误差分别为24.09%和1.57%,经过5次调谐后两者误差分别降为2.33%和1.39%,验证了调谐算法的有效性。该调谐算法具有普适性,也可以用于其他频率的RFQ,将来还可以促进质子加速器装置的小型化,推动医用质子装置的普及。展开更多
Radio frequency quadrupoles(RFQs),which are crucial components of proton injectors,significantly affect the performance of proton accelerator facilities.An RFQ with a high frequency of 714 MHz dedicated to compact pro...Radio frequency quadrupoles(RFQs),which are crucial components of proton injectors,significantly affect the performance of proton accelerator facilities.An RFQ with a high frequency of 714 MHz dedicated to compact proton injectors for medi-cal applications is designed in this study.The RFQ is designed to accelerate proton beams from 50 keV to 4 MeV within a short length of 2 m and can be matched closely with the downstream drift tube linac to capture more particles through a preliminary optimization.To develop an advanced RFQ,challenging techniques,including fabrication and tuning method,must be evaluated and verified using a prototype.An aluminium prototype is derived from the conceptual design of the RFQ and then redesigned to confirm the radio frequency performance,fabrication procedure,and feasibility of the tuning algorithm.Eventually,a new tuning algorithm based on the response matrix and least-squares method is developed,which yields favorable results based on the prototype,i.e.,the errors of the dipole and quadrupole components reduced to a low level after several tuning iterations.Benefiting from the conceptual design and techniques obtained from the prototype,the formal mechanical design of the 2-m RFQ is ready for the next manufacturing step.展开更多
To validate the design rationality of the power coupler for the RFQ cavity and minimize cavity contamination,we designed a low-loss offline conditioning cavity and conducted high-power testing.This offline cavity feat...To validate the design rationality of the power coupler for the RFQ cavity and minimize cavity contamination,we designed a low-loss offline conditioning cavity and conducted high-power testing.This offline cavity features two coupling ports and two tuners,operating at a frequency of 162.5 MHz with a tuning range of 3.2 MHz.Adjusting the installation angle of the coupling ring and the insertion depth of the tuner helps minimize cavity losses.We performed electromagnetic structural and multiphysics simulations,revealing a minimal theoretical power loss of 4.3%.However,when the cavity frequency varied by110 kHz,theoretical power losses increased to10%,necessitating constant tuner adjustments during conditioning.Multiphysics simulations indicated that increased cavity temperature did not affect frequency variation.Upon completion of the offline high-power conditioning platform,we measured the transmission performance,revealing a power loss of 6.3%,exceeding the theoretical calculation.Conditioning utilized efficient automatic range scanning and standing wave resonant methods.To fully condition the power coupler,a 15°phase difference between two standing wave points in the condition-ing system was necessary.Notably,the maximum continuous wave power surpassed 20 kW,exceeding the expected target.展开更多
Separated Function RFQ (SFRFQ) was proposed as a post accelerator of RFQ to accelerate heavy ions at low frequency. It introduces gap accelerating in the quadrupole electrodes, and therefore it has higher accelerating...Separated Function RFQ (SFRFQ) was proposed as a post accelerator of RFQ to accelerate heavy ions at low frequency. It introduces gap accelerating in the quadrupole electrodes, and therefore it has higher accelerating efficiency than the conventional RFQ accelerator. The first SFRFQ prototype cavity has been specially designed and constructed as a post accelerator to accelerate O+ beam from 1.03 MeV to 1.64 MeV. Based on accomplishment of low power measurement and high power test, the beam commissioning was carried out to verify its feasibility. The measured energy gain per cell of SFRFQ is 45 keV, which is about 60% higher than that of Peking University Integral Split Ring (ISR) RFQ.展开更多
A new linear accelerating structure SFRFQ was proposed to transfer the RFQ inter-vane voltage to the inter-longitudinal accelerating gap voltage so as to improve the acceleration efficiency.A SFRFQ prototype is being ...A new linear accelerating structure SFRFQ was proposed to transfer the RFQ inter-vane voltage to the inter-longitudinal accelerating gap voltage so as to improve the acceleration efficiency.A SFRFQ prototype is being constructed to explore its feasibilities,which will be installed behind the 1MeV ISR RFQ and accelerates the O^+ beam from 1MeV to 1.6MeV.A high power SFRFQ model cavity was designed and tested,which has proved that an accelerating voltaire higher than 70kV could be applied.A magnetic triplet matching section was designed to realize the beam matching between 1MeV ISR RFQ and SFRFQ.The upgrading of 1MeV ISR RFQ has been carried out smoothly, and its output beam current has reached 2mA.展开更多
The physics design of a 3 MeV, 30 mA, 352.2 MHz Radio Frequency Quadrupole (RFQ) is done for the future Indian Spallation Neutron Source (ISNS) project at RRCAT, India. The beam dynamics design of RFQ and the error an...The physics design of a 3 MeV, 30 mA, 352.2 MHz Radio Frequency Quadrupole (RFQ) is done for the future Indian Spallation Neutron Source (ISNS) project at RRCAT, India. The beam dynamics design of RFQ and the error analysis of the input beam parameters are done by using standard beam dynamics code PARMTEQM. The electromagnetic stu-dies for the two-dimensional and three-dimensional cavity design are performed using computer codes SUPERFISH and CST Microwave Studio. The physics design of RFQ consisting of the beam dynamics design near the beam axis and the electromagnetic design for the RFQ resonator is described here.展开更多
文摘中国散裂中子源研发了一台射频四极RFQ(Radio Frequency Quadrupole)强流质子加速器。为保证RFQ顺利出束,对加工焊接阶段、RF调谐调场、高功率RF(Radio Frequency)老练过程中出现的问题进行了分析,给出了解决办法,并进行了调束实验。三坐标测量测得RFQ精加工后的加工公差约在20μm,RFQ腔体无载品质因子Q0大于7 679,约为理论无载Q0值的80%。RFQ腔内RF电场分布的平整度好于2.5%,RFQ高功率RF老练入腔功率达到450 k W,是理论腔耗390 k W的1.15倍,且保持连续12 h不打火。在RFQ调束实验中,RFQ出口得到3 Me V、28 m A的负氢束流,满足中国散裂中子源的要求。
文摘SSC-Linac RFQ(Separated Sector Cyclotron Linac Radio Frequency Quadrupolec)是中国科学院近代物理研究所和北京大学共同研制的国内首台高电荷态强流重离子连续波四杆型加速器,机械加工的高精度是RFQ能否顺利出束的关键步骤之一。为了检测其机械形位公差,采用了激光跟踪仪和关节测量臂合理组合应用的测量新方法,使两种高精度的测量仪器能扬长避短,克服了大尺度工件形位公差传统测量方法的不足,使其在测量过程中发挥其最优的使用性和操作性,有效地提高了工作效率,从而保证RFQ高精度的测量结果。
文摘射频四极场加速器(Radio Frequency Quadrupole,RFQ)广泛应用于质子加速器装置中,高频率、紧凑型RFQ的发展可以推动质子加速器装置的小型化,同时也面临调谐困难的问题。紧凑型RFQ的性能对腔体尺寸的敏感度高,基于理论物理特性的传统调谐算法难以取得良好效果,而基于腔体实际物理特性的调谐算法则可以解决紧凑型RFQ的调谐难点。本文提出了一种基于响应矩阵和最小二乘法的调谐算法,该算法可以限定求解的范围,避免计算结果超出调谐器可调谐范围的问题;为二极场分量赋予权重,可以高效地降低二极场误差,解决二极场分量难以调谐的问题。根据新的调谐算法分别在模拟环境下的RFQ样机上完成了调谐实验,在搭建的测量平台获得的结果显示:初始状态下二、四极场误差分别为24.09%和1.57%,经过5次调谐后两者误差分别降为2.33%和1.39%,验证了调谐算法的有效性。该调谐算法具有普适性,也可以用于其他频率的RFQ,将来还可以促进质子加速器装置的小型化,推动医用质子装置的普及。
基金This work was supported by National Natural Science Foundation of China(No.12222513).
文摘Radio frequency quadrupoles(RFQs),which are crucial components of proton injectors,significantly affect the performance of proton accelerator facilities.An RFQ with a high frequency of 714 MHz dedicated to compact proton injectors for medi-cal applications is designed in this study.The RFQ is designed to accelerate proton beams from 50 keV to 4 MeV within a short length of 2 m and can be matched closely with the downstream drift tube linac to capture more particles through a preliminary optimization.To develop an advanced RFQ,challenging techniques,including fabrication and tuning method,must be evaluated and verified using a prototype.An aluminium prototype is derived from the conceptual design of the RFQ and then redesigned to confirm the radio frequency performance,fabrication procedure,and feasibility of the tuning algorithm.Eventually,a new tuning algorithm based on the response matrix and least-squares method is developed,which yields favorable results based on the prototype,i.e.,the errors of the dipole and quadrupole components reduced to a low level after several tuning iterations.Benefiting from the conceptual design and techniques obtained from the prototype,the formal mechanical design of the 2-m RFQ is ready for the next manufacturing step.
基金supported by the Chinese initiative accelerator driven subcritical system and the hundred talents plan of the Chinese Academy of Sciences(No.E129841Y).
文摘To validate the design rationality of the power coupler for the RFQ cavity and minimize cavity contamination,we designed a low-loss offline conditioning cavity and conducted high-power testing.This offline cavity features two coupling ports and two tuners,operating at a frequency of 162.5 MHz with a tuning range of 3.2 MHz.Adjusting the installation angle of the coupling ring and the insertion depth of the tuner helps minimize cavity losses.We performed electromagnetic structural and multiphysics simulations,revealing a minimal theoretical power loss of 4.3%.However,when the cavity frequency varied by110 kHz,theoretical power losses increased to10%,necessitating constant tuner adjustments during conditioning.Multiphysics simulations indicated that increased cavity temperature did not affect frequency variation.Upon completion of the offline high-power conditioning platform,we measured the transmission performance,revealing a power loss of 6.3%,exceeding the theoretical calculation.Conditioning utilized efficient automatic range scanning and standing wave resonant methods.To fully condition the power coupler,a 15°phase difference between two standing wave points in the condition-ing system was necessary.Notably,the maximum continuous wave power surpassed 20 kW,exceeding the expected target.
基金supported by the National Natural Science Foundation of China (Grand No. 10905003)China Postdoctoral Science Foundation
文摘Separated Function RFQ (SFRFQ) was proposed as a post accelerator of RFQ to accelerate heavy ions at low frequency. It introduces gap accelerating in the quadrupole electrodes, and therefore it has higher accelerating efficiency than the conventional RFQ accelerator. The first SFRFQ prototype cavity has been specially designed and constructed as a post accelerator to accelerate O+ beam from 1.03 MeV to 1.64 MeV. Based on accomplishment of low power measurement and high power test, the beam commissioning was carried out to verify its feasibility. The measured energy gain per cell of SFRFQ is 45 keV, which is about 60% higher than that of Peking University Integral Split Ring (ISR) RFQ.
文摘A new linear accelerating structure SFRFQ was proposed to transfer the RFQ inter-vane voltage to the inter-longitudinal accelerating gap voltage so as to improve the acceleration efficiency.A SFRFQ prototype is being constructed to explore its feasibilities,which will be installed behind the 1MeV ISR RFQ and accelerates the O^+ beam from 1MeV to 1.6MeV.A high power SFRFQ model cavity was designed and tested,which has proved that an accelerating voltaire higher than 70kV could be applied.A magnetic triplet matching section was designed to realize the beam matching between 1MeV ISR RFQ and SFRFQ.The upgrading of 1MeV ISR RFQ has been carried out smoothly, and its output beam current has reached 2mA.
文摘The physics design of a 3 MeV, 30 mA, 352.2 MHz Radio Frequency Quadrupole (RFQ) is done for the future Indian Spallation Neutron Source (ISNS) project at RRCAT, India. The beam dynamics design of RFQ and the error analysis of the input beam parameters are done by using standard beam dynamics code PARMTEQM. The electromagnetic stu-dies for the two-dimensional and three-dimensional cavity design are performed using computer codes SUPERFISH and CST Microwave Studio. The physics design of RFQ consisting of the beam dynamics design near the beam axis and the electromagnetic design for the RFQ resonator is described here.
