In this experimental study, involving deuterium–deuterium fusion neutron emission spectroscopy measurement on the experimental advanced superconducting tokamak(EAST), a liquid scintillator detector(BC501 A) was emplo...In this experimental study, involving deuterium–deuterium fusion neutron emission spectroscopy measurement on the experimental advanced superconducting tokamak(EAST), a liquid scintillator detector(BC501 A) was employed. This decision was based on the detector's superior sensitivity, optimal time-response, and its exceptional n–γ discrimination capability. This detector emits fast pulse signals that are as narrow as 100 ns, with high count rates that can peak at several Mcps. However, conventional nuclear circuits faced challenges in performing pulse height analysis, n–γ pulse shape discrimination, and in recording the entire pulse waveform under such high count rate conditions. To address these challenges, a high-speed digital pulse signal acquisition and processing system was designed. The system was developed around a micro-telecommunications computing architecture. Within this structure, a signal acquisition and processing(SAQP) module communicated through PCI Express links, achieving a bandwidth of up to 1.6 GB/s. To accurately capture the detailed shape of the pulses, four channels of analog-to-digital converters were used, each with a 500-MSPS sampling rate and a 14-bit resolution, ensuring an accuracy that surpassed 11 bits. An n–γ discrimination algorithm, based on the two-gate integral method, was also developed. Implemented within field programmable gate arrays, this algorithm provided a real-time n–γ discrimination spectrum for pulse height analysis. The system underwent rigorous testing in a laboratory setting and during an EAST experiment. The results confirmed that the innovative SAQP system can satisfy the demanding requirements of high-parameter experiments, manage count rates of up to 2 Mcps, execute real-time n–γ discrimination algorithms, and record entire pulse waveforms without any data loss.展开更多
Objective:The Chinese ADS proton Linac injector I composed of an electron cyclotron resonance ion source,a lowenergy beam transport line,a radio frequency quadrupole(RFQ)accelerator,a medium-energy beam transport(MEBT...Objective:The Chinese ADS proton Linac injector I composed of an electron cyclotron resonance ion source,a lowenergy beam transport line,a radio frequency quadrupole(RFQ)accelerator,a medium-energy beam transport(MEBT)line,a superconducting section and beam dump with design goal to achieve CW proton beam with beam current 10 mA and energy gain around 10 MeV.In order to maintain the stability of the RF system,to compensate for the beam load effect and to provide the GUI required for the operation of the RF power system,we have established a LLRF control system.Methods:This LLRF system for ADS proton Linac injector I in IHEP consists of RF reference system and LLRF controllers for oneRFQcavity,twoMEBTbunching cavities and 14 superconductive spoke cavities.We have adopted a new development mTCA.4-based hardware platform,and it has some characteristics such as faster bandwidth,standardized design,easy operation and maintenance and good expansibility.Results:The LLRF system has been improved and optimized and has now been put into operation.It takes into account the pulse and CW beam flow mode,feedforward and feedback control functions.Conclusion:With the help of this system,we achieved stable operationwith narrowpulses,long pulses,andCWmodes under different beam loads.This article describes the implementation of this system and presents some initial the CW beam acceleration results with the help of this system at the end of 2016.展开更多
基金supported by the Users with Excellence Program of the Hefei Science Center CAS (No. 2020HSC-UE012)the Comprehensive Research Facility for Fusion Technology Program of China (No. 2018-000052-73-01-001228)the Institute of Energy,Hefei Comprehensive National Science Center (Nos. 21KZS205, 21KZL401 and 22KZZ502)。
文摘In this experimental study, involving deuterium–deuterium fusion neutron emission spectroscopy measurement on the experimental advanced superconducting tokamak(EAST), a liquid scintillator detector(BC501 A) was employed. This decision was based on the detector's superior sensitivity, optimal time-response, and its exceptional n–γ discrimination capability. This detector emits fast pulse signals that are as narrow as 100 ns, with high count rates that can peak at several Mcps. However, conventional nuclear circuits faced challenges in performing pulse height analysis, n–γ pulse shape discrimination, and in recording the entire pulse waveform under such high count rate conditions. To address these challenges, a high-speed digital pulse signal acquisition and processing system was designed. The system was developed around a micro-telecommunications computing architecture. Within this structure, a signal acquisition and processing(SAQP) module communicated through PCI Express links, achieving a bandwidth of up to 1.6 GB/s. To accurately capture the detailed shape of the pulses, four channels of analog-to-digital converters were used, each with a 500-MSPS sampling rate and a 14-bit resolution, ensuring an accuracy that surpassed 11 bits. An n–γ discrimination algorithm, based on the two-gate integral method, was also developed. Implemented within field programmable gate arrays, this algorithm provided a real-time n–γ discrimination spectrum for pulse height analysis. The system underwent rigorous testing in a laboratory setting and during an EAST experiment. The results confirmed that the innovative SAQP system can satisfy the demanding requirements of high-parameter experiments, manage count rates of up to 2 Mcps, execute real-time n–γ discrimination algorithms, and record entire pulse waveforms without any data loss.
文摘Objective:The Chinese ADS proton Linac injector I composed of an electron cyclotron resonance ion source,a lowenergy beam transport line,a radio frequency quadrupole(RFQ)accelerator,a medium-energy beam transport(MEBT)line,a superconducting section and beam dump with design goal to achieve CW proton beam with beam current 10 mA and energy gain around 10 MeV.In order to maintain the stability of the RF system,to compensate for the beam load effect and to provide the GUI required for the operation of the RF power system,we have established a LLRF control system.Methods:This LLRF system for ADS proton Linac injector I in IHEP consists of RF reference system and LLRF controllers for oneRFQcavity,twoMEBTbunching cavities and 14 superconductive spoke cavities.We have adopted a new development mTCA.4-based hardware platform,and it has some characteristics such as faster bandwidth,standardized design,easy operation and maintenance and good expansibility.Results:The LLRF system has been improved and optimized and has now been put into operation.It takes into account the pulse and CW beam flow mode,feedforward and feedback control functions.Conclusion:With the help of this system,we achieved stable operationwith narrowpulses,long pulses,andCWmodes under different beam loads.This article describes the implementation of this system and presents some initial the CW beam acceleration results with the help of this system at the end of 2016.
