To further improve the performance of acceler-ators,the first cryogenic normal-conducting RF gun in China was designed and manufactured.As a new and attractive trend,this optimized cryogenic RF gun can generate a low-...To further improve the performance of acceler-ators,the first cryogenic normal-conducting RF gun in China was designed and manufactured.As a new and attractive trend,this optimized cryogenic RF gun can generate a low-emittance beam with a short-driven laser pulse because of its promising high gradient on the cath-ode.In this paper,optimization of the RF design and beam dynamics,including suppression of the peak RF field and elimination of the multipole mode,is presented.In addi-tion,the emittance growth caused by the alignment devi-ation and RF jitter is discussed.After the gun was manufactured,a cold test was conducted at both room temperature and cryogenic conditions.At room tempera-ture,the field distribution was obtained by the bead pull method.Under cryogenic conditions,the RF properties,such as the coupling coefficient and quality factor,varied with temperature.The test results agreed with the design.In the cryogenic test,vibration measurements were performed.Without vibration isolation,a maximum vibration of 50 lm was observed.These cold test results are the basis of the following high-power test.展开更多
Purpose Recent researches of RF gun operated at cryogenic temperature have many advantages to serve as the technology to realize the future light source.In order to further improve the accelerating gradient of acceler...Purpose Recent researches of RF gun operated at cryogenic temperature have many advantages to serve as the technology to realize the future light source.In order to further improve the accelerating gradient of accelerators,the cryogenic acceleration structure is studied.Design/methodology/approach The cryogenic accelerating structure is studied by numerical analysis and simulation.Findings In this paper,the low-temperature characteristics of the material are analyzedfirstly,and then the preliminary design scheme of the cavity is proposed according to the analysis results.Furthermore,the prototype with RF coupler is designed and optimized systemically,and the modified Poynting vector distribution is calculated.Finally,the high-power test based on existed setup is also proposed.Originality/value The study of the cryogenic structure in this paper is helpful for improving the accelerating gradient and developing compact accelerators.展开更多
基金supported by the National Key R&D Program of China(No.2018YFF0109203)ANSO(ANSO-CR-KP-2020-16).
文摘To further improve the performance of acceler-ators,the first cryogenic normal-conducting RF gun in China was designed and manufactured.As a new and attractive trend,this optimized cryogenic RF gun can generate a low-emittance beam with a short-driven laser pulse because of its promising high gradient on the cath-ode.In this paper,optimization of the RF design and beam dynamics,including suppression of the peak RF field and elimination of the multipole mode,is presented.In addi-tion,the emittance growth caused by the alignment devi-ation and RF jitter is discussed.After the gun was manufactured,a cold test was conducted at both room temperature and cryogenic conditions.At room tempera-ture,the field distribution was obtained by the bead pull method.Under cryogenic conditions,the RF properties,such as the coupling coefficient and quality factor,varied with temperature.The test results agreed with the design.In the cryogenic test,vibration measurements were performed.Without vibration isolation,a maximum vibration of 50 lm was observed.These cold test results are the basis of the following high-power test.
文摘Purpose Recent researches of RF gun operated at cryogenic temperature have many advantages to serve as the technology to realize the future light source.In order to further improve the accelerating gradient of accelerators,the cryogenic acceleration structure is studied.Design/methodology/approach The cryogenic accelerating structure is studied by numerical analysis and simulation.Findings In this paper,the low-temperature characteristics of the material are analyzedfirstly,and then the preliminary design scheme of the cavity is proposed according to the analysis results.Furthermore,the prototype with RF coupler is designed and optimized systemically,and the modified Poynting vector distribution is calculated.Finally,the high-power test based on existed setup is also proposed.Originality/value The study of the cryogenic structure in this paper is helpful for improving the accelerating gradient and developing compact accelerators.