Although the deuterium and helium have almost the same mass,a Penning Optical Gas Analyzer(POGA) system on the basis of the spectroscopic method and Penning discharging has been designed on EAST,since 2014.The POGA ...Although the deuterium and helium have almost the same mass,a Penning Optical Gas Analyzer(POGA) system on the basis of the spectroscopic method and Penning discharging has been designed on EAST,since 2014.The POGA system was developed successfully in 2015,it was the first time that EAST could detect helium partial pressure in deuterium plasma(wall conditioning and plasma operation scenario).With dedicated calibration and proper adjustment of the parameters,the minimum concentration of helium in deuterium gas can be measured as about 0.5% instead of 1% on the other tokamak devices.Moreover,the He and D2 partial pressures are measured simultaneously.At present,the measurable range of deuterium partial pressure is 1×10^-7 mbar to 1×10^-5mbar,meanwhile the range of helium is 1×10^-8 mbar to 1×10^-5 mbar.The measurable range can be modified by means of the adjustment of POGA system's parameters.It is possible to detect the interesting part of the gas with a time resolution of less than 5 ms(the 200 ms because of conductance of transfer pipe at present).The POGA system was routinely employed to wall conditioning and helium enrichment investigation in2015.Last but not the least,the low temperature plasma of POGA is generated by normal penning gauge Pfeiffer IKR gauge instead of Alcatel CF2 P,which has been suspended for a few years and was used for almost all the POGA systems in the world.展开更多
Parameters of hydrogen plasma in a miniature Penning discharge ion source, including the electron temperature and the electron density, were measured by using double probes. The results indicate that the electron dens...Parameters of hydrogen plasma in a miniature Penning discharge ion source, including the electron temperature and the electron density, were measured by using double probes. The results indicate that the electron density increases and the electron temperature decreases with the increase in gas pressure and the discharge current. The electron temperature is about 5 - 9 eV and the electron density is 6.0× 10^13 ~ 1.2 × 10^14 m^-3 while the discharge current is in a range of 50 - 120 μA.展开更多
For the purpose of producing high intensity, multiply charged metal ion beams, the dual hollow cathode ion source for metal ions (DUHOCAMIS) was derived from the hot cathode Penning ion source combined with the holl...For the purpose of producing high intensity, multiply charged metal ion beams, the dual hollow cathode ion source for metal ions (DUHOCAMIS) was derived from the hot cathode Penning ion source combined with the hollow cathode sputtering experiments in 2007. To investigate the behavior of this discharge geometry in a stronger magnetic bottle-shaped field, a new test bench for DUHOCAMIS with a high magnetic bottle-shaped field up to 0.6 T has been set up at the Peking University. The experiments with magnetic fields from 0.13 T to 0.52 T have indicated that the discharge behavior is very sensitive to the magnetic flux densities. The slope of discharge curves in a very wide range can be controlled by changing the magnetic field as well as regulated by adjusting the cathode heating power; the production of metallic ions would be much greater than gas ions with the increased magnetic flux density; and the magnetic field has a much higher influence on the DHCD mode than on the PIG mode.展开更多
基金funded by National Magnetic Confinement Fusion Science Program of China under Contract No.2013GB114004,No.2014GB106005 & No.2015GB101000National Nature Science Foundation of China under Contract No.11625524,No.11321092 and No.11405210partly supported by the Japan Society for the Promotion of ScienceNational Research Foundation of Korea-National Science Foundation of China(JSPS-NRF-NSFC) A3 Foresight Program in the field of Plasma Physics(NSFC No.11261140328)
文摘Although the deuterium and helium have almost the same mass,a Penning Optical Gas Analyzer(POGA) system on the basis of the spectroscopic method and Penning discharging has been designed on EAST,since 2014.The POGA system was developed successfully in 2015,it was the first time that EAST could detect helium partial pressure in deuterium plasma(wall conditioning and plasma operation scenario).With dedicated calibration and proper adjustment of the parameters,the minimum concentration of helium in deuterium gas can be measured as about 0.5% instead of 1% on the other tokamak devices.Moreover,the He and D2 partial pressures are measured simultaneously.At present,the measurable range of deuterium partial pressure is 1×10^-7 mbar to 1×10^-5mbar,meanwhile the range of helium is 1×10^-8 mbar to 1×10^-5 mbar.The measurable range can be modified by means of the adjustment of POGA system's parameters.It is possible to detect the interesting part of the gas with a time resolution of less than 5 ms(the 200 ms because of conductance of transfer pipe at present).The POGA system was routinely employed to wall conditioning and helium enrichment investigation in2015.Last but not the least,the low temperature plasma of POGA is generated by normal penning gauge Pfeiffer IKR gauge instead of Alcatel CF2 P,which has been suspended for a few years and was used for almost all the POGA systems in the world.
文摘Parameters of hydrogen plasma in a miniature Penning discharge ion source, including the electron temperature and the electron density, were measured by using double probes. The results indicate that the electron density increases and the electron temperature decreases with the increase in gas pressure and the discharge current. The electron temperature is about 5 - 9 eV and the electron density is 6.0× 10^13 ~ 1.2 × 10^14 m^-3 while the discharge current is in a range of 50 - 120 μA.
基金Supported by National Natural Science Foundation of China(11105008,10775011)
文摘For the purpose of producing high intensity, multiply charged metal ion beams, the dual hollow cathode ion source for metal ions (DUHOCAMIS) was derived from the hot cathode Penning ion source combined with the hollow cathode sputtering experiments in 2007. To investigate the behavior of this discharge geometry in a stronger magnetic bottle-shaped field, a new test bench for DUHOCAMIS with a high magnetic bottle-shaped field up to 0.6 T has been set up at the Peking University. The experiments with magnetic fields from 0.13 T to 0.52 T have indicated that the discharge behavior is very sensitive to the magnetic flux densities. The slope of discharge curves in a very wide range can be controlled by changing the magnetic field as well as regulated by adjusting the cathode heating power; the production of metallic ions would be much greater than gas ions with the increased magnetic flux density; and the magnetic field has a much higher influence on the DHCD mode than on the PIG mode.