A normal-pressure MWPC detector for position measurement of intermediate and high energy radioactive ionsat RIBLL2 has been fabricated, which has a sensitive area of 75 mm100 mm and contains of three wire planes.Fig....A normal-pressure MWPC detector for position measurement of intermediate and high energy radioactive ionsat RIBLL2 has been fabricated, which has a sensitive area of 75 mm100 mm and contains of three wire planes.Fig. 1 shows the layout of the MWPC wire planes.The anode plane is sandwiched between two cathodeplanes, and the anode-cathode spacing is 4 mm. Theanode plane consisted of 15 m gold-plated tungstenwires with a pitch of 2 mm. The cathode planes Xand Y , made of 60 m stainless steel wires with apitch of 0.5 mm, and every adjacent four wires are sol-dered together to form one readout strip of 2 mm inwidth. The wire directions in X and Y are orthogonalto each other, the wire direction in anode is parallel tothe wire direction in Y .展开更多
Radon and its decay daughters are one of the main sources of natural radiation to humans and the second leading cause of lung cancer after smoking[1].In this paper,a new multi-wire impulse ionization chamber type inte...Radon and its decay daughters are one of the main sources of natural radiation to humans and the second leading cause of lung cancer after smoking[1].In this paper,a new multi-wire impulse ionization chamber type intended for continuous airborne radon activity measurements is described.展开更多
One-nucleon knockout reactions have been used to get spectroscopic factor information of unstable nuclei for decadesl[1-4],and a systematic analysis of experiment for intermediate energies of around 80 MeV/u knockout ...One-nucleon knockout reactions have been used to get spectroscopic factor information of unstable nuclei for decadesl[1-4],and a systematic analysis of experiment for intermediate energies of around 80 MeV/u knockout reactions based on the eikonal model indicates a strong isospin asymmetry dependence of the reduction of the extracted spectroscopic strength relative to the shell-model predictionsl[2,3].展开更多
The Heavy-ion Medical Machine(HIMM),which is the first commercial medical accelerator designed and built independently by the Institute of Modern Physics(IMP,CAS)in Wuwei,Gansu Province,China,had officially started cl...The Heavy-ion Medical Machine(HIMM),which is the first commercial medical accelerator designed and built independently by the Institute of Modern Physics(IMP,CAS)in Wuwei,Gansu Province,China,had officially started clinical therapy.展开更多
CEE(CSR External-target Experiment)will be the first large-scale nuclear physics experiment device running in GeV energy region based on the domestic nuclear physics big scientific device HIRFL-CSR.
A Fission-Parallel Plate Avalanche Counter(Fission-PPAC)has been developed for fast neutron measurements[1].The detector consists two sets of PPAC,where a ^(238)U(U_(3)O_(8))coating is put in the second set of PPAC as...A Fission-Parallel Plate Avalanche Counter(Fission-PPAC)has been developed for fast neutron measurements[1].The detector consists two sets of PPAC,where a ^(238)U(U_(3)O_(8))coating is put in the second set of PPAC as show in Fig.1(a)and physical map show in Fig.1(b).^(252)Cf source emits an spontaneous fission fragment and a neutron,the neutron passes through PPAC 1 and may be detected by PPAC 2 with a ^(238)U(U_(3)O_(8))coating.The total thickness of ^(238)U(U_(3)O_(8))is 600g/cm^(2),while the detection efficiency attain 8×10^(7).展开更多
Situated at the middle of the second Radioactive Ion Beam Line in Lanzhou(RIBLL2),the External Target Facility(ETF)has been constructed for reaction studies with high-energy secondary beams of several hundred MeV/u.Th...Situated at the middle of the second Radioactive Ion Beam Line in Lanzhou(RIBLL2),the External Target Facility(ETF)has been constructed for reaction studies with high-energy secondary beams of several hundred MeV/u.The charged fragment detector system of ETF consists of a dipole magnet,tracking drift chambers,ionization chambers and plastic scintillators for particle identification via B-ΔE-TOF method.After more than ten years of R&D on detectors,electronics,data acquisition system and data analysis framework,the charged fragment detector system of ETF has completed its test runs and ready to produce scientific data。展开更多
A Photon-ion coincidence system for projectile X-ray emission in ion-atom collisions in HIRFL-CSRe internal target is constructed.The system consists of X-ray detectors,ion detectors,signal process electronics and dat...A Photon-ion coincidence system for projectile X-ray emission in ion-atom collisions in HIRFL-CSRe internal target is constructed.The system consists of X-ray detectors,ion detectors,signal process electronics and data acquisition(DAQ)system.The photon detector which used for detecting the low energy X-rays are combined with HpGe,Si(Li),Silicon drift detector(SDD)and crystal spectrometer(CS).The ion detectors which used to measure charged-particle trajectories are multi-wire proportional chamber(MWPC).The main purpose of the signal process electronics which using standard NIM electronics is converting the analogue signals from the photon and ion detectors into a format suitable for physics analysis.The DAQ system is based on VME bus and the maximum integrated data acquisition system(MIDAS)developed at Paul Scherrer Institute in Switzerland and TRIUMF in Canada.展开更多
The Fission-PPAC is a neutron monitor device,can use in reactor of ADS in Institute of Modern Physics,Chinese Academy of Sciences.Neutron can not be detected directly.Fast neutron can induce fission of 238U target and...The Fission-PPAC is a neutron monitor device,can use in reactor of ADS in Institute of Modern Physics,Chinese Academy of Sciences.Neutron can not be detected directly.Fast neutron can induce fission of 238U target and 238U atom split into two fission fragments.What we measure is the ionizing electron of working gas from fission fragment.Because PPAC is fast time detector,to obtain higher electron drift velocity and large signal,we must choose a suitable working gas.展开更多
A position-sensitive MWPC detector based on LC delay-line readout has been developed for precise position measurement for experimental studies of nuclear physics.The detector consists of six electrode wire planes,whic...A position-sensitive MWPC detector based on LC delay-line readout has been developed for precise position measurement for experimental studies of nuclear physics.The detector consists of six electrode wire planes,which is placed in a gas chamber with a sensitive area of 100 mm×80 mm.Fig.1 shows a schematic drawing with the disposition of the six wire planes.This structure has two anode planes,each is sandwiched between two cathode planes,and the anode-cathode spacing is 4 mm.The anode plane,consist of 15 m gold-plated tungsten wires with a pitch of 3 mm.The two cathode pairs are positioned in such a way that the wires are perpendicular to each other in order to give positions at X and Y directions.The cathode planes in each pair are parallel each other in the orientation of the wires,which are made of 30 m stainless steel wires with a pitch of 0.5 mm.展开更多
文摘A normal-pressure MWPC detector for position measurement of intermediate and high energy radioactive ionsat RIBLL2 has been fabricated, which has a sensitive area of 75 mm100 mm and contains of three wire planes.Fig. 1 shows the layout of the MWPC wire planes.The anode plane is sandwiched between two cathodeplanes, and the anode-cathode spacing is 4 mm. Theanode plane consisted of 15 m gold-plated tungstenwires with a pitch of 2 mm. The cathode planes Xand Y , made of 60 m stainless steel wires with apitch of 0.5 mm, and every adjacent four wires are sol-dered together to form one readout strip of 2 mm inwidth. The wire directions in X and Y are orthogonalto each other, the wire direction in anode is parallel tothe wire direction in Y .
文摘Radon and its decay daughters are one of the main sources of natural radiation to humans and the second leading cause of lung cancer after smoking[1].In this paper,a new multi-wire impulse ionization chamber type intended for continuous airborne radon activity measurements is described.
基金National Natural Science Foundation of China(11575257,U1732134,11305222)。
文摘One-nucleon knockout reactions have been used to get spectroscopic factor information of unstable nuclei for decadesl[1-4],and a systematic analysis of experiment for intermediate energies of around 80 MeV/u knockout reactions based on the eikonal model indicates a strong isospin asymmetry dependence of the reduction of the extracted spectroscopic strength relative to the shell-model predictionsl[2,3].
基金National Natural Science Foundation of China(U11775281,U11815301)。
文摘The Heavy-ion Medical Machine(HIMM),which is the first commercial medical accelerator designed and built independently by the Institute of Modern Physics(IMP,CAS)in Wuwei,Gansu Province,China,had officially started clinical therapy.
文摘CEE(CSR External-target Experiment)will be the first large-scale nuclear physics experiment device running in GeV energy region based on the domestic nuclear physics big scientific device HIRFL-CSR.
基金National Natural Science Foundation of China(U1432123,11575268,11875301,11675238)。
文摘A Fission-Parallel Plate Avalanche Counter(Fission-PPAC)has been developed for fast neutron measurements[1].The detector consists two sets of PPAC,where a ^(238)U(U_(3)O_(8))coating is put in the second set of PPAC as show in Fig.1(a)and physical map show in Fig.1(b).^(252)Cf source emits an spontaneous fission fragment and a neutron,the neutron passes through PPAC 1 and may be detected by PPAC 2 with a ^(238)U(U_(3)O_(8))coating.The total thickness of ^(238)U(U_(3)O_(8))is 600g/cm^(2),while the detection efficiency attain 8×10^(7).
基金National Natural Science Foundation of China(U1732134,11575257,11305222)。
文摘Situated at the middle of the second Radioactive Ion Beam Line in Lanzhou(RIBLL2),the External Target Facility(ETF)has been constructed for reaction studies with high-energy secondary beams of several hundred MeV/u.The charged fragment detector system of ETF consists of a dipole magnet,tracking drift chambers,ionization chambers and plastic scintillators for particle identification via B-ΔE-TOF method.After more than ten years of R&D on detectors,electronics,data acquisition system and data analysis framework,the charged fragment detector system of ETF has completed its test runs and ready to produce scientific data。
文摘A Photon-ion coincidence system for projectile X-ray emission in ion-atom collisions in HIRFL-CSRe internal target is constructed.The system consists of X-ray detectors,ion detectors,signal process electronics and data acquisition(DAQ)system.The photon detector which used for detecting the low energy X-rays are combined with HpGe,Si(Li),Silicon drift detector(SDD)and crystal spectrometer(CS).The ion detectors which used to measure charged-particle trajectories are multi-wire proportional chamber(MWPC).The main purpose of the signal process electronics which using standard NIM electronics is converting the analogue signals from the photon and ion detectors into a format suitable for physics analysis.The DAQ system is based on VME bus and the maximum integrated data acquisition system(MIDAS)developed at Paul Scherrer Institute in Switzerland and TRIUMF in Canada.
文摘The Fission-PPAC is a neutron monitor device,can use in reactor of ADS in Institute of Modern Physics,Chinese Academy of Sciences.Neutron can not be detected directly.Fast neutron can induce fission of 238U target and 238U atom split into two fission fragments.What we measure is the ionizing electron of working gas from fission fragment.Because PPAC is fast time detector,to obtain higher electron drift velocity and large signal,we must choose a suitable working gas.
文摘A position-sensitive MWPC detector based on LC delay-line readout has been developed for precise position measurement for experimental studies of nuclear physics.The detector consists of six electrode wire planes,which is placed in a gas chamber with a sensitive area of 100 mm×80 mm.Fig.1 shows a schematic drawing with the disposition of the six wire planes.This structure has two anode planes,each is sandwiched between two cathode planes,and the anode-cathode spacing is 4 mm.The anode plane,consist of 15 m gold-plated tungsten wires with a pitch of 3 mm.The two cathode pairs are positioned in such a way that the wires are perpendicular to each other in order to give positions at X and Y directions.The cathode planes in each pair are parallel each other in the orientation of the wires,which are made of 30 m stainless steel wires with a pitch of 0.5 mm.
