Purpose To study the cosmic ray muon tomographic imaging of high-Z material with Micromegas-based tracking system.Method A high-spatial-resolution tracking system was set up with the micro-mesh gaseous structure(Micro...Purpose To study the cosmic ray muon tomographic imaging of high-Z material with Micromegas-based tracking system.Method A high-spatial-resolution tracking system was set up with the micro-mesh gaseous structure(Micromegas)detec-tors in order to study the muon tomographic imaging technique.Six layers of 90 mm×90 mm one-dimensional readout Micromegas were used to construct a tracking system.Result and conclusion The imaging test using some metallic bars was performed with cosmic ray muons.A two-dimensional imaging of the test object was presented with a newly proposed ratio algorithm.The result of this work shows that the ratio algorithm is well performed.展开更多
In this paper we report the results of Micromegas prototypes constructed by attaching micromesh to an anode using thermo-bond films. The excellent metal attaching ability and good dielectical property of this kind of ...In this paper we report the results of Micromegas prototypes constructed by attaching micromesh to an anode using thermo-bond films. The excellent metal attaching ability and good dielectical property of this kind of film make it a promising material to be used as avalanche gap spacers. Several prototypes are successfully made. The electron transmission properties are first studied and then the gas gain is measured in argon-isobutane mixtures. The maximum gain of more than 104 is easily obtained. The energy resolutions for 55Fe 5.9 keV K~ ray can be better than 20% over one magnitude in gain for different operational gas mixtures and the best energy resolution of 13.7% （FWHM） can be achieved with the gas mixture of 94% argon concentration. The preliminary test results of the prototypes with sensitive area of 45 mm×45 mm without internal support show good uniformity across the sensitive area.展开更多
Micromegas （MICRO MEsh GAseous Structure） is a position-sensitive gaseous detector. It is widely used in particle physics. We present the results of full 3D Monte Carlo simulations of Micromegas performance, taking ...Micromegas （MICRO MEsh GAseous Structure） is a position-sensitive gaseous detector. It is widely used in particle physics. We present the results of full 3D Monte Carlo simulations of Micromegas performance, taking into account all the processes from the primary ionization, the elctron collection efficiency, and the gain to the signal formation. The simulation results are in good agreement with experimental data.展开更多
In this paper Micromegas has been designed to detect neutrons. The simulation of the spatial resolution of Micromegas as neutron detector is carried out by GEANT4 toolkit. The neutron track reconstruction method based...In this paper Micromegas has been designed to detect neutrons. The simulation of the spatial resolution of Micromegas as neutron detector is carried out by GEANT4 toolkit. The neutron track reconstruction method based on the time coincidence technology is employed in the present work. The influence of the flux of incident 14 MeV neutron and high gamma background on the spatial resolution is carefully studied. Our results show that the spatial resolution of the detector is sensitive to the neutron flux, but insensitive to the intensity of γ background if the neutron track reconstruction method proposed by our group is used. The γ insensitivity makes it possible for us to use the Micromegas detector under condition which has high γ-rays background.展开更多
The structure of micromegas （micro-mesh gaseous structure） detectors with different micro-meshes of stainless steel wire woven netting and Ni foil has been presented. The counting rates, energy resolution, gain, dis...The structure of micromegas （micro-mesh gaseous structure） detectors with different micro-meshes of stainless steel wire woven netting and Ni foil has been presented. The counting rates, energy resolution, gain, discharge probability and time resolution have been measured. Wider counter plateaus and gain for the developed detector were obtained. Excellent energy resolution of the micromegas detector, 17% （FWHM） based on Ni foil micro-mesh and 25% （FWHM） based on stainless steel wire woven netting micro-mesh, has been obtained for the 5.9 keV photon peak of the 55Fe X-ray source in an At/CO2（10%） gas mixture. The best time resolution at -620 V micro-mesh voltage and -870 V drift voltage is 14.8 ns for cosmic rays in an Ar/CO2 （10%） gas mixture. These results satisfy the basic demand of the micromegas detector preliminary design.展开更多
The design and performance of a Micromegas with a resistive anode are presented in this paper. A thin resistive sheet with volume resistivity of 10^12 Ω·cm is glued onto the readout electrode surface and its per...The design and performance of a Micromegas with a resistive anode are presented in this paper. A thin resistive sheet with volume resistivity of 10^12 Ω·cm is glued onto the readout electrode surface and its performance is investigated by using a 55Fe X-ray radioactive source in the operation gas of argon and isobutene mixtures （Ar/Iso=95/5）. The gas gain at different mesh high voltage, counting rate and working time are given. Energy spectra at different working voltages are measured and the results are discussed. We have oberved that a Micromegas with a resistive anode can be operated at higer gain than a standard Micromegas without sparks.展开更多
In this paper, we present a study of a micromegas detector prototype built with bulk technology. Following a short discussion of the micromegas detector＇s structure and working mechanism, the bulk fabrication process...In this paper, we present a study of a micromegas detector prototype built with bulk technology. Following a short discussion of the micromegas detector＇s structure and working mechanism, the bulk fabrication process is described, and some testing results of the prototype are presented.展开更多
This work shows the results of a streamer discharge mode studies in various gas detectors developed up-to-date. The results are based on a new experimental data from high-speed thin-gap gas detector application develo...This work shows the results of a streamer discharge mode studies in various gas detectors developed up-to-date. The results are based on a new experimental data from high-speed thin-gap gas detector application developments as well as on basic knowledge of multi-wire devices operations.展开更多
基金supported by the Program of National Natural Science Foundation of China Grant No.11605197the Fundamental Research Funds for the Central Universitiesthe State Key Laboratory of Particle Detection and Electronics,SKLPDE-ZZ-201818,SKLPDE-KF-201912
文摘Purpose To study the cosmic ray muon tomographic imaging of high-Z material with Micromegas-based tracking system.Method A high-spatial-resolution tracking system was set up with the micro-mesh gaseous structure(Micromegas)detec-tors in order to study the muon tomographic imaging technique.Six layers of 90 mm×90 mm one-dimensional readout Micromegas were used to construct a tracking system.Result and conclusion The imaging test using some metallic bars was performed with cosmic ray muons.A two-dimensional imaging of the test object was presented with a newly proposed ratio algorithm.The result of this work shows that the ratio algorithm is well performed.
基金Supported by National Natural Science Foundation of China (10775132)
文摘In this paper we report the results of Micromegas prototypes constructed by attaching micromesh to an anode using thermo-bond films. The excellent metal attaching ability and good dielectical property of this kind of film make it a promising material to be used as avalanche gap spacers. Several prototypes are successfully made. The electron transmission properties are first studied and then the gas gain is measured in argon-isobutane mixtures. The maximum gain of more than 104 is easily obtained. The energy resolutions for 55Fe 5.9 keV K~ ray can be better than 20% over one magnitude in gain for different operational gas mixtures and the best energy resolution of 13.7% （FWHM） can be achieved with the gas mixture of 94% argon concentration. The preliminary test results of the prototypes with sensitive area of 45 mm×45 mm without internal support show good uniformity across the sensitive area.
基金Supported by National Natural Science Foundation of China (10775132)
文摘Micromegas （MICRO MEsh GAseous Structure） is a position-sensitive gaseous detector. It is widely used in particle physics. We present the results of full 3D Monte Carlo simulations of Micromegas performance, taking into account all the processes from the primary ionization, the elctron collection efficiency, and the gain to the signal formation. The simulation results are in good agreement with experimental data.
基金Supported by National Natural Science Foundation of China (10575046, 10775062)
文摘In this paper Micromegas has been designed to detect neutrons. The simulation of the spatial resolution of Micromegas as neutron detector is carried out by GEANT4 toolkit. The neutron track reconstruction method based on the time coincidence technology is employed in the present work. The influence of the flux of incident 14 MeV neutron and high gamma background on the spatial resolution is carefully studied. Our results show that the spatial resolution of the detector is sensitive to the neutron flux, but insensitive to the intensity of γ background if the neutron track reconstruction method proposed by our group is used. The γ insensitivity makes it possible for us to use the Micromegas detector under condition which has high γ-rays background.
基金Supported by National Natural Science Foundation of China (10575046,10775062)Program for New Century Excellent Talents in University
文摘The structure of micromegas （micro-mesh gaseous structure） detectors with different micro-meshes of stainless steel wire woven netting and Ni foil has been presented. The counting rates, energy resolution, gain, discharge probability and time resolution have been measured. Wider counter plateaus and gain for the developed detector were obtained. Excellent energy resolution of the micromegas detector, 17% （FWHM） based on Ni foil micro-mesh and 25% （FWHM） based on stainless steel wire woven netting micro-mesh, has been obtained for the 5.9 keV photon peak of the 55Fe X-ray source in an At/CO2（10%） gas mixture. The best time resolution at -620 V micro-mesh voltage and -870 V drift voltage is 14.8 ns for cosmic rays in an Ar/CO2 （10%） gas mixture. These results satisfy the basic demand of the micromegas detector preliminary design.
文摘The design and performance of a Micromegas with a resistive anode are presented in this paper. A thin resistive sheet with volume resistivity of 10^12 Ω·cm is glued onto the readout electrode surface and its performance is investigated by using a 55Fe X-ray radioactive source in the operation gas of argon and isobutene mixtures （Ar/Iso=95/5）. The gas gain at different mesh high voltage, counting rate and working time are given. Energy spectra at different working voltages are measured and the results are discussed. We have oberved that a Micromegas with a resistive anode can be operated at higer gain than a standard Micromegas without sparks.
文摘In this paper, we present a study of a micromegas detector prototype built with bulk technology. Following a short discussion of the micromegas detector＇s structure and working mechanism, the bulk fabrication process is described, and some testing results of the prototype are presented.
文摘This work shows the results of a streamer discharge mode studies in various gas detectors developed up-to-date. The results are based on a new experimental data from high-speed thin-gap gas detector application developments as well as on basic knowledge of multi-wire devices operations.
