Graphite is applied to many applications in the field of atomic energy. In the design of nuclear reactors, such as ADS, HTGRs and fusion reactors, graphite is among the primary candidate materials for a reflector zone...Graphite is applied to many applications in the field of atomic energy. In the design of nuclear reactors, such as ADS, HTGRs and fusion reactors, graphite is among the primary candidate materials for a reflector zone to soften the neutron spectrum. Moreover, the accurate prediction of tritium breeding ratio and nuclear heating rate sets the necessity of using adequate nuclear data for carbon since they have strong influence on the feasibility of the overall design of fusion reactors.展开更多
The Accelerator-Driven Systems (ADS) is mainly used for nuclear transmutation of long-lived fission products, fuel breeding and energy production. China has started to develop the ADS project and is now underway vigor...The Accelerator-Driven Systems (ADS) is mainly used for nuclear transmutation of long-lived fission products, fuel breeding and energy production. China has started to develop the ADS project and is now underway vigorously.The combination of nuclear data with a Monte Carlo transportation code like MCNP-4C is widely applied to design such kind of nuclear engineering facilities. The integral experiment is conducted to benchmark the nuclear data, involved in design calculations, both with regard to the activation and the particle transport behavior.展开更多
The symmetry energy at the time of the production of intermediate mass fragments(IMFs) is studied using experimentally observed IMF multiplicities combined with quantum statistical model calculations(QSM of Hahn and S...The symmetry energy at the time of the production of intermediate mass fragments(IMFs) is studied using experimentally observed IMF multiplicities combined with quantum statistical model calculations(QSM of Hahn and St cker).The ratios of difference in chemical potentials between neutrons and protons relative to the temperature,(μn-μp)/T,and the double ratio temperature,T,were extracted experimentally in the reactions of64,70Zn,64Ni+58,64Ni,112,124Sn,197Au,232Th at 40A MeV.The extracted(μn-μp)/TTscales linearly with δNN,where δNN is the asymmetry parameter,(N-Z)/A,of the emitting source and(μn-μp)/T=(11.1 1.4)δNN0.21 was derived.The experimentally extracted(μn-μp)/T and the double ratio temperatures are compared with those from the QSM calculations.The temperatures-,T,and densities,ρ,extracted from the(μn-μp)/T values agreed with those from the double ratio thermometer which used the yield ratios of d,t,h and α particles.However the two analyses of the differential chemical potential analysis and the initial temperature analysis end up almost identical relation between T and ρ.T=5.25±0.75 MeV is evaluated from the(μn-μp)/Tanalysis,but no density determination was possible.From the extracted T value,the symmetry energy coefficient Esym =14.6±3.5 MeV is determined for the emitting source of T=5.25±0.75 MeV.展开更多
An experimental method was used to evaluate the primary isotope yields of semi-central collisions in the reaction system64Zn+112Sn at 40A MeV.The characteristic nature of the hot nuclear matter at the time of the isot...An experimental method was used to evaluate the primary isotope yields of semi-central collisions in the reaction system64Zn+112Sn at 40A MeV.The characteristic nature of the hot nuclear matter at the time of the isotope formation was studied.The multiplicities of light particles(LPs) associated with intermediate mass fragments(IMFs) were determined experimentally by using a kinematical focusing technique.The primary isotope distributions,reconstructed by a Monte Carlo method,were compared with those of the AMD-Gemini simulations.ac/T=0.11 and asym/T=3.34 were extracted from the reconstructed primary fragments yield.These are consistent with those of the primary fragments of the AMD simulation.展开更多
Type I X-ray bursts are the most frequent thermonuclear explosions in nature,resulting from thermonuclear runaway on the surface of an accreting neutron star[1].The breakout reaction 14O(α ,p)17F from the hot CNO cyc...Type I X-ray bursts are the most frequent thermonuclear explosions in nature,resulting from thermonuclear runaway on the surface of an accreting neutron star[1].The breakout reaction 14O(α ,p)17F from the hot CNO cycle may have a prominent impact on the burst light curve and burst ashes[2].However,insufficient experimental information is available to calculate a reliable,precise rate for this reaction[3].We proposed to address the experimental investigation of the 14O(α,p)17F using Time Projection Chamber(TPC)[4].展开更多
文摘Graphite is applied to many applications in the field of atomic energy. In the design of nuclear reactors, such as ADS, HTGRs and fusion reactors, graphite is among the primary candidate materials for a reflector zone to soften the neutron spectrum. Moreover, the accurate prediction of tritium breeding ratio and nuclear heating rate sets the necessity of using adequate nuclear data for carbon since they have strong influence on the feasibility of the overall design of fusion reactors.
文摘The Accelerator-Driven Systems (ADS) is mainly used for nuclear transmutation of long-lived fission products, fuel breeding and energy production. China has started to develop the ADS project and is now underway vigorously.The combination of nuclear data with a Monte Carlo transportation code like MCNP-4C is widely applied to design such kind of nuclear engineering facilities. The integral experiment is conducted to benchmark the nuclear data, involved in design calculations, both with regard to the activation and the particle transport behavior.
基金Supported by National Natural Science Foundation of China(NSFC) Projects (No.11075189)"100 Persons Project(Nos.0910020BR0 and Y010110BR0)"+2 种基金"ADS project 302"of the Chinese Academy of Sciences(No.Y103010ADS)supported by U.S.Department of Energy(Grant No.DE-FG03-93ER40773)Robert A.Welch Foundation(Grant A0330)
文摘The symmetry energy at the time of the production of intermediate mass fragments(IMFs) is studied using experimentally observed IMF multiplicities combined with quantum statistical model calculations(QSM of Hahn and St cker).The ratios of difference in chemical potentials between neutrons and protons relative to the temperature,(μn-μp)/T,and the double ratio temperature,T,were extracted experimentally in the reactions of64,70Zn,64Ni+58,64Ni,112,124Sn,197Au,232Th at 40A MeV.The extracted(μn-μp)/TTscales linearly with δNN,where δNN is the asymmetry parameter,(N-Z)/A,of the emitting source and(μn-μp)/T=(11.1 1.4)δNN0.21 was derived.The experimentally extracted(μn-μp)/T and the double ratio temperatures are compared with those from the QSM calculations.The temperatures-,T,and densities,ρ,extracted from the(μn-μp)/T values agreed with those from the double ratio thermometer which used the yield ratios of d,t,h and α particles.However the two analyses of the differential chemical potential analysis and the initial temperature analysis end up almost identical relation between T and ρ.T=5.25±0.75 MeV is evaluated from the(μn-μp)/Tanalysis,but no density determination was possible.From the extracted T value,the symmetry energy coefficient Esym =14.6±3.5 MeV is determined for the emitting source of T=5.25±0.75 MeV.
基金Supported by National Natural Science Foundation of China(NSFC) Projects (No.11075189)"100 Persons Project"(Nos.0910020BR0 and Y010110BR0)+2 种基金"ADS project 302"(No.Y103010ADS)of Chinese Academy of Sciencessupported by the U.S.Department of Energy under Grant No.DE-FG0393ER40773the Robert A.Welch Foundation under Grant A0330
文摘An experimental method was used to evaluate the primary isotope yields of semi-central collisions in the reaction system64Zn+112Sn at 40A MeV.The characteristic nature of the hot nuclear matter at the time of the isotope formation was studied.The multiplicities of light particles(LPs) associated with intermediate mass fragments(IMFs) were determined experimentally by using a kinematical focusing technique.The primary isotope distributions,reconstructed by a Monte Carlo method,were compared with those of the AMD-Gemini simulations.ac/T=0.11 and asym/T=3.34 were extracted from the reconstructed primary fragments yield.These are consistent with those of the primary fragments of the AMD simulation.
文摘Type I X-ray bursts are the most frequent thermonuclear explosions in nature,resulting from thermonuclear runaway on the surface of an accreting neutron star[1].The breakout reaction 14O(α ,p)17F from the hot CNO cycle may have a prominent impact on the burst light curve and burst ashes[2].However,insufficient experimental information is available to calculate a reliable,precise rate for this reaction[3].We proposed to address the experimental investigation of the 14O(α,p)17F using Time Projection Chamber(TPC)[4].
