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
Many laboratories in the world have built telescope arrays based on silicon strip position-sensitive detectors such as MUST2^([1]),However,these methods lack detec-tion and identi cation capability of a large number o...Many laboratories in the world have built telescope arrays based on silicon strip position-sensitive detectors such as MUST2^([1]),However,these methods lack detec-tion and identi cation capability of a large number of low-energy particles produced over a wide range of beam en-ergies.To improve the present experimental capabilities,we have developed a trapezoid-shaped Frisch-grid ioniza-tion chamber(TFG-IC)as part of a telescope system to cover the identi cation of low-energy incident particles.展开更多
Heavy ion collision experiments are one of the important means to study the properties of nuclear matter.The CSR External-target Experiment(CEE)is a low-temperature,high-density nuclear matter measurement spectrom-ete...Heavy ion collision experiments are one of the important means to study the properties of nuclear matter.The CSR External-target Experiment(CEE)is a low-temperature,high-density nuclear matter measurement spectrom-eter used for heavy ion collision experiments,and it will become the rst large-scale nuclear physics experimental facility in China to operate in the GeV energy range after its completion.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
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Many laboratories in the world have built telescope arrays based on silicon strip position-sensitive detectors such as MUST2^([1]),However,these methods lack detec-tion and identi cation capability of a large number of low-energy particles produced over a wide range of beam en-ergies.To improve the present experimental capabilities,we have developed a trapezoid-shaped Frisch-grid ioniza-tion chamber(TFG-IC)as part of a telescope system to cover the identi cation of low-energy incident particles.
文摘Heavy ion collision experiments are one of the important means to study the properties of nuclear matter.The CSR External-target Experiment(CEE)is a low-temperature,high-density nuclear matter measurement spectrom-eter used for heavy ion collision experiments,and it will become the rst large-scale nuclear physics experimental facility in China to operate in the GeV energy range after its completion.
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).
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.
