We experimentally studied ion behavior and interelectrode breakdown voltage. The ion behavior of a drift tube directly influences the detection of ion intensity, and then influences the detection sensitivity of a syst...We experimentally studied ion behavior and interelectrode breakdown voltage. The ion behavior of a drift tube directly influences the detection of ion intensity, and then influences the detection sensitivity of a system. Interelectrode voltage and pressure directly influence the ion behavior. Gas discharge between electrodes influences the adjustments required for interelectrode voltage. The experimental results show： ion intensity increases exponentially with the increment of voltage between drift electrodes; ion intensity decreases exponentially as pressure increases; with the increment of pressure, the breakdown voltage at first decreases, and then increases; ion injection has a significant influence on breakdown voltage, and this influence depends on the pressure and shapes of the electrodes. We explain the results above through assumptions and by mathematical methods.展开更多
A hybrid single cavity （HSC） linac, which is formed by combining a radio frequency quadrupole （RFQ） and a drift tube （DT） structure into one interdigital-H （IH） cavity, is fabricated and assembled as a proof o...A hybrid single cavity （HSC） linac, which is formed by combining a radio frequency quadrupole （RFQ） and a drift tube （DT） structure into one interdigital-H （IH） cavity, is fabricated and assembled as a proof of principle injector for cancer therapy synchrotron, based on the culmination of several years of research. The HSC linac adopts a direct plasma injection scheme （DPIS）, which can inject a high intensity heavy ion beam produced by a laser ion source （LIS）. The input beam current of the HSC is designed to be 20 mAC6＋ ions. According to numerical simulations, the HSC linac can accelerate a 6-mA C6＋beam, which meets the requirement of the needed particle number for cancer therapy （10s-9 ions/pulse）. The HSC injector with the DPIS method makes the existing multi- turn injection system and stripping system unnecessary, and can also bring down the size of the beam pipe in existing synchrotron magnets, which could reduce the whole cost of synchrotron. The radio frequency （rf） measurements show excellent rf properties for the resonator, with a measured Q equal to 91% of the simulated value. A C6＋ ion beam extracted from the LIS was used for the HSC commissioning. In beam testing, we found the measured beam parameters agreed with simulations. More details of the measurements and the results of the high power test are reported in this paper.展开更多
基金Supported by Financial Support from the National Major Scientific Instruments and Equipment Development Special Funds(2011YQ030113)National Recruitment Program of Global Experts(NRPGE)+1 种基金the Hundred Talents Program of Sichuan Province(HTPSP)the Startup Funding of Sichuan University for Setting up the Research Center of Analytical Instrumentation
文摘We experimentally studied ion behavior and interelectrode breakdown voltage. The ion behavior of a drift tube directly influences the detection of ion intensity, and then influences the detection sensitivity of a system. Interelectrode voltage and pressure directly influence the ion behavior. Gas discharge between electrodes influences the adjustments required for interelectrode voltage. The experimental results show： ion intensity increases exponentially with the increment of voltage between drift electrodes; ion intensity decreases exponentially as pressure increases; with the increment of pressure, the breakdown voltage at first decreases, and then increases; ion injection has a significant influence on breakdown voltage, and this influence depends on the pressure and shapes of the electrodes. We explain the results above through assumptions and by mathematical methods.
基金Supported by the National Natural Science Foundation of China(Grant No.60706030,20827007)the National High-Tech Research and Development Program of China(863 Program)(Grant No.2007AA04Z337)
基金Supported by National Natural Science Foundation of China and One Hundred Person Project of CAS
文摘A hybrid single cavity （HSC） linac, which is formed by combining a radio frequency quadrupole （RFQ） and a drift tube （DT） structure into one interdigital-H （IH） cavity, is fabricated and assembled as a proof of principle injector for cancer therapy synchrotron, based on the culmination of several years of research. The HSC linac adopts a direct plasma injection scheme （DPIS）, which can inject a high intensity heavy ion beam produced by a laser ion source （LIS）. The input beam current of the HSC is designed to be 20 mAC6＋ ions. According to numerical simulations, the HSC linac can accelerate a 6-mA C6＋beam, which meets the requirement of the needed particle number for cancer therapy （10s-9 ions/pulse）. The HSC injector with the DPIS method makes the existing multi- turn injection system and stripping system unnecessary, and can also bring down the size of the beam pipe in existing synchrotron magnets, which could reduce the whole cost of synchrotron. The radio frequency （rf） measurements show excellent rf properties for the resonator, with a measured Q equal to 91% of the simulated value. A C6＋ ion beam extracted from the LIS was used for the HSC commissioning. In beam testing, we found the measured beam parameters agreed with simulations. More details of the measurements and the results of the high power test are reported in this paper.
