为了监测并分析合肥光源运行过程中的束流损失特性,开发了一套基于闪烁体探测器、条带电极束流位置监测器(Beam Position Monitor,BPM)和高速示波器的高时间分辨束流损失及束团位置同步监测系统。通过仿真与实测波形对比,验证了系统输...为了监测并分析合肥光源运行过程中的束流损失特性,开发了一套基于闪烁体探测器、条带电极束流位置监测器(Beam Position Monitor,BPM)和高速示波器的高时间分辨束流损失及束团位置同步监测系统。通过仿真与实测波形对比,验证了系统输出束损脉冲波形的准确性。基于非对称高斯函数拟合的方法提取了束损脉冲信号特征参数。基于高速示波器的逐束团三维位置及电荷量精确测量软件包(High-speed Oscilloscopebased Three-dimensional bunch-by-bunch Charge And Position measurement,HOTCAP)从条带电极信号中提取了逐束团电荷量及位置信息。基于合肥光源储存环的特殊填充模式实现束损数据和BPM数据束团编号的关联对齐。利用该系统监测了合肥光源注入瞬态及注入后稳态运行条件下的束损情况。结果表明:稳态运行过程中逐束团束损与电荷量分布呈现显著关联性,与随机束损的理论预期相符;注入瞬态过程中首次观察到补注束团及其之后第14个储存束团同时存在显著束损的现象。展开更多
A compact TM_(020)-mode RF cavity was proposed and studied by KEK and RIKEN for the storage ring of the NanoTerasu facility.However,performance limitations due to accelerating mode leakage into the coaxial slots have ...A compact TM_(020)-mode RF cavity was proposed and studied by KEK and RIKEN for the storage ring of the NanoTerasu facility.However,performance limitations due to accelerating mode leakage into the coaxial slots have been identified.This paper presents an improved TM_(020)-mode cavity design to solve this issue.By employing an elliptical choke,the leakage power can be significantly reduced.Harmful parasitic modes other than the TM_(020)-mode are effectively suppressed using the elliptical choke placed at the magnetic node of the TM_(020)-mode.Through optimization,this improved TM_(020)-mode RF cavity meets the requirements of the Super Tau-Charm Facility(STCF)collider rings with a beam current of up to 2 A.Detailed mechanical design and thermal analysis confirm the feasibility and stability of the improved cavity.展开更多
Schottky mass spectrometry utilizing heavy-ion storage rings is a powerful technique for the precise mass and decay half-life measurements of highly charged ions.Owing to the nondestructive ion detection features of S...Schottky mass spectrometry utilizing heavy-ion storage rings is a powerful technique for the precise mass and decay half-life measurements of highly charged ions.Owing to the nondestructive ion detection features of Schottky noise detectors,the number of stored ions in the ring is determined by the peak area in the measured revolution frequency spectrum.Because of their intrinsic amplitude-frequency characteristic(AFC),Schottky detector systems exhibit varying sensitivities at different frequencies.Using low-energy electron-cooled stored ions,a new method is developed to calibrate the AFC curve of the Schottky detector system of the Experimental Cooler Storage Ring(CSRe)storage ring located in Lanzhou,China.Using the amplitude-calibrated frequency spectrum,a notable refinement was observed in the precision of both the peak position and peak area.As a result,the storage lifetimes of the electron-cooled fully ionized^(56)Fe^(26+)ions were determined with high precision at beam energies of 13.7 and 116.4 MeV/u,despite of frequency drifts during the experiment.When electron cooling was turned off,the effective vacuum condition experienced by the 116.4 MeV/u^(56)Fe^(26+)ions was determined using amplitude-calibrated spectra,revealing a value of 2×10^(−10)mbar,which is consistent with vacuum gauge readings along the CSRe ring.The method reported herein will be adapted for the next-generation storage ring of the HIAF facility under construction in Huizhou,China.It can also be adapted to other storage ring facilities worldwide to improve precision and enhance lifetime measurements using many ions in the ring.展开更多
The Cooling Storage Ring of the Heavy Ion Research Facility in Lanzhou(HIRFL-CSR)was constructed to study nuclear physics,atomic physics,interdisciplinary science,and related applications.The External Target Facility(...The Cooling Storage Ring of the Heavy Ion Research Facility in Lanzhou(HIRFL-CSR)was constructed to study nuclear physics,atomic physics,interdisciplinary science,and related applications.The External Target Facility(ETF)is located in the main ring of the HIRFL-CSR.The gamma detector of the ETF is built to measure emitted gamma rays with energies below 5 MeV in the center-of-mass frame and is planned to measure light fragments with energies up to 300 MeV.The readout electronics for the gamma detector were designed and commissioned.The readout electronics consist of thirty-two front-end cards,thirty-two readout control units(RCUs),one common readout unit,one synchronization&clock unit,and one sub-trigger unit.By using the real-time peak-detection algorithm implemented in the RCU,the data volume can be significantly reduced.In addition,trigger logic selection algorithms are implemented to improve the selection of useful events and reduce the data size.The test results show that the integral nonlinearity of the readout electronics is less than 1%,and the energy resolution for measuring the 60 Co source is better than 5.5%.This study discusses the design and performance of the readout electronics.展开更多
文摘为了监测并分析合肥光源运行过程中的束流损失特性,开发了一套基于闪烁体探测器、条带电极束流位置监测器(Beam Position Monitor,BPM)和高速示波器的高时间分辨束流损失及束团位置同步监测系统。通过仿真与实测波形对比,验证了系统输出束损脉冲波形的准确性。基于非对称高斯函数拟合的方法提取了束损脉冲信号特征参数。基于高速示波器的逐束团三维位置及电荷量精确测量软件包(High-speed Oscilloscopebased Three-dimensional bunch-by-bunch Charge And Position measurement,HOTCAP)从条带电极信号中提取了逐束团电荷量及位置信息。基于合肥光源储存环的特殊填充模式实现束损数据和BPM数据束团编号的关联对齐。利用该系统监测了合肥光源注入瞬态及注入后稳态运行条件下的束损情况。结果表明:稳态运行过程中逐束团束损与电荷量分布呈现显著关联性,与随机束损的理论预期相符;注入瞬态过程中首次观察到补注束团及其之后第14个储存束团同时存在显著束损的现象。
基金supported by the“Hundred Talents Program”of the Chinese Academy of Sciences(No.KJ2310007003)the Fundamental Research Funds for the Central Universities(Nos.WK2310000114,KY2310000047,and KY2310000067)+1 种基金the Chinese Academy of Sciences President’s International Fellowship Initiative(No.2025PD0102)Super Tau-Charm Facility key technology research project。
文摘A compact TM_(020)-mode RF cavity was proposed and studied by KEK and RIKEN for the storage ring of the NanoTerasu facility.However,performance limitations due to accelerating mode leakage into the coaxial slots have been identified.This paper presents an improved TM_(020)-mode cavity design to solve this issue.By employing an elliptical choke,the leakage power can be significantly reduced.Harmful parasitic modes other than the TM_(020)-mode are effectively suppressed using the elliptical choke placed at the magnetic node of the TM_(020)-mode.Through optimization,this improved TM_(020)-mode RF cavity meets the requirements of the Super Tau-Charm Facility(STCF)collider rings with a beam current of up to 2 A.Detailed mechanical design and thermal analysis confirm the feasibility and stability of the improved cavity.
基金supported by the National Key R&D Program of China (No. 2023YFA1606401 and 2018YFA0404401)the Young Scholar of Regional Development,CAS ([2023] 15)+1 种基金Chinese Academy of Sciences Stable Support for Young Teams in Basic Research (No. YSBR-002)Special Fund for Strategic Pilot Technology of Chinese Academy of Sciences (No. XDB34000000)
文摘Schottky mass spectrometry utilizing heavy-ion storage rings is a powerful technique for the precise mass and decay half-life measurements of highly charged ions.Owing to the nondestructive ion detection features of Schottky noise detectors,the number of stored ions in the ring is determined by the peak area in the measured revolution frequency spectrum.Because of their intrinsic amplitude-frequency characteristic(AFC),Schottky detector systems exhibit varying sensitivities at different frequencies.Using low-energy electron-cooled stored ions,a new method is developed to calibrate the AFC curve of the Schottky detector system of the Experimental Cooler Storage Ring(CSRe)storage ring located in Lanzhou,China.Using the amplitude-calibrated frequency spectrum,a notable refinement was observed in the precision of both the peak position and peak area.As a result,the storage lifetimes of the electron-cooled fully ionized^(56)Fe^(26+)ions were determined with high precision at beam energies of 13.7 and 116.4 MeV/u,despite of frequency drifts during the experiment.When electron cooling was turned off,the effective vacuum condition experienced by the 116.4 MeV/u^(56)Fe^(26+)ions was determined using amplitude-calibrated spectra,revealing a value of 2×10^(−10)mbar,which is consistent with vacuum gauge readings along the CSRe ring.The method reported herein will be adapted for the next-generation storage ring of the HIAF facility under construction in Huizhou,China.It can also be adapted to other storage ring facilities worldwide to improve precision and enhance lifetime measurements using many ions in the ring.
基金supported by the National Natural Science Foundation of China (Nos. 12222512, 12375193, U2031206, U1831206, and U2032209)the Scientific Instrument Developing Project of the Chinese Academy of Sciences (GJJSTD20210009)+1 种基金the CAS Pioneer Hundred Talent Programthe CAS Light of West China Program
文摘The Cooling Storage Ring of the Heavy Ion Research Facility in Lanzhou(HIRFL-CSR)was constructed to study nuclear physics,atomic physics,interdisciplinary science,and related applications.The External Target Facility(ETF)is located in the main ring of the HIRFL-CSR.The gamma detector of the ETF is built to measure emitted gamma rays with energies below 5 MeV in the center-of-mass frame and is planned to measure light fragments with energies up to 300 MeV.The readout electronics for the gamma detector were designed and commissioned.The readout electronics consist of thirty-two front-end cards,thirty-two readout control units(RCUs),one common readout unit,one synchronization&clock unit,and one sub-trigger unit.By using the real-time peak-detection algorithm implemented in the RCU,the data volume can be significantly reduced.In addition,trigger logic selection algorithms are implemented to improve the selection of useful events and reduce the data size.The test results show that the integral nonlinearity of the readout electronics is less than 1%,and the energy resolution for measuring the 60 Co source is better than 5.5%.This study discusses the design and performance of the readout electronics.
