2009 Vol. 26, No. 4
Display Method:
2009, 26(4): 275-281.
doi: 10.11804/NuclPhysRev.26.04.275
Abstract:
Research on the properties of nuclei around the “Island of inversion” is current focus of nuclear physics. In this paper， at first，the experimental progress of nuclei around the “Island of inversion” is reviewed. Then， the progress of theoretical models is introduced,including the developments and results of mean field model， shell model， HartreeFock model and macroscopicmicroscopic model. Emphasis of the theoretical discussions is placed on the macroscopicmicroscopic model. In addition，the achievements and differences of these theoretical models are discussed briefly.
Key words:
Research on the properties of nuclei around the “Island of inversion” is current focus of nuclear physics. In this paper， at first，the experimental progress of nuclei around the “Island of inversion” is reviewed. Then， the progress of theoretical models is introduced,including the developments and results of mean field model， shell model， HartreeFock model and macroscopicmicroscopic model. Emphasis of the theoretical discussions is placed on the macroscopicmicroscopic model. In addition，the achievements and differences of these theoretical models are discussed briefly.
Key words:
2009, 26(4): 282-287.
doi: 10.11804/NuclPhysRev.26.04.282
Abstract:
By analyzing carefully the inbeam γ spectroscopy data of odd-odd 174Re, we have extracted the branching ratios of the interband and intraband E2 γ transitions from the two rotational bands of different configurations in 174Re.The ratios of the reduced transition probabilities B(E2) have been deduced and analyzed using a band mixing theory. Information on the band interaction and deformation have been obtained. Apparent differences of transition quadrupole moments are found in the two configurations. A likely reason for the differences in the transition quadrupole moments is the shape driving effects of 1/2-[541] quasiproton or 1/2-[521] quasineutron, which has been proposed in the odd-A neighbors of 174Re.
By analyzing carefully the inbeam γ spectroscopy data of odd-odd 174Re, we have extracted the branching ratios of the interband and intraband E2 γ transitions from the two rotational bands of different configurations in 174Re.The ratios of the reduced transition probabilities B(E2) have been deduced and analyzed using a band mixing theory. Information on the band interaction and deformation have been obtained. Apparent differences of transition quadrupole moments are found in the two configurations. A likely reason for the differences in the transition quadrupole moments is the shape driving effects of 1/2-[541] quasiproton or 1/2-[521] quasineutron, which has been proposed in the odd-A neighbors of 174Re.
2009, 26(4): 288-293.
doi: 10.11804/NuclPhysRev.26.04.288
Abstract:
The theoretical models of the cluster structures of the light neutronrich nuclei as well as the corresponding physical mechanism and experimental approaches by breakup reaction have been introduced， which may serve as references for possible experimental studies of the cluster structure of light neutronrich nuclei.
The theoretical models of the cluster structures of the light neutronrich nuclei as well as the corresponding physical mechanism and experimental approaches by breakup reaction have been introduced， which may serve as references for possible experimental studies of the cluster structure of light neutronrich nuclei.
2009, 26(4): 294-299.
doi: 10.11804/NuclPhysRev.26.04.294
Abstract:
The study of the splittings between the masses of mesons with different spin and orbit quantum numbers is important for checking the quark potential model. In the previous calculations with quark potential models, the splitting between ηc and J/ψ is however too small to the experimental result. In this paper the mass splitting of ηcJ/ψ and the splitting between the new
meson ηb and Υ(1s) are investigated with the complete Breit quark potential regularized by applying the form factor μ2/(q2+μ2) one time in momentum space. In addition, because the complete Breit potential includes the spinorbit interaction, it can be used to investigate the splittings among χc0, χc1
and χc2. The investigated results indicate that the screen mass μ in the form factor of regularization is related to the reduced mass of meson.
The splittings of ηc-J/ψ, ηbΥ, and χc0χc1χc2 can reproduce the experimental results with high accuracy when the screen mass is expanded to the thirdorder polynomial of meson reduced mass.
The study of the splittings between the masses of mesons with different spin and orbit quantum numbers is important for checking the quark potential model. In the previous calculations with quark potential models, the splitting between ηc and J/ψ is however too small to the experimental result. In this paper the mass splitting of ηcJ/ψ and the splitting between the new
meson ηb and Υ(1s) are investigated with the complete Breit quark potential regularized by applying the form factor μ2/(q2+μ2) one time in momentum space. In addition, because the complete Breit potential includes the spinorbit interaction, it can be used to investigate the splittings among χc0, χc1
and χc2. The investigated results indicate that the screen mass μ in the form factor of regularization is related to the reduced mass of meson.
The splittings of ηc-J/ψ, ηbΥ, and χc0χc1χc2 can reproduce the experimental results with high accuracy when the screen mass is expanded to the thirdorder polynomial of meson reduced mass.
2009, 26(4): 300-303.
doi: 10.11804/NuclPhysRev.26.04.300
Abstract:
We investigate the imaging of pionemitting source produced in NN=200 GeV Au+Au collisions with NeXSPheRIO model. The pictures of the system evolution show that there is obvious inhomogeneous structure of granular lumps. The results of imaging analysis indicate that the relative source functions for the various events of the granular sources are different even though the events are with the same impact parameter. This difference is more evident for the events with large impact parameter.
We investigate the imaging of pionemitting source produced in NN=200 GeV Au+Au collisions with NeXSPheRIO model. The pictures of the system evolution show that there is obvious inhomogeneous structure of granular lumps. The results of imaging analysis indicate that the relative source functions for the various events of the granular sources are different even though the events are with the same impact parameter. This difference is more evident for the events with large impact parameter.
2009, 26(4): 304-307.
doi: 10.11804/NuclPhysRev.26.04.304
Abstract:
Based on the property of wigner function， the Wigner function of charged Linear Harmonic Oscillator in noncommutative space was obtained by considering the noncommutative of the coordinatecoordinate in the relation of space variable.
Based on the property of wigner function， the Wigner function of charged Linear Harmonic Oscillator in noncommutative space was obtained by considering the noncommutative of the coordinatecoordinate in the relation of space variable.
2009, 26(4): 308-311.
doi: 10.11804/NuclPhysRev.26.04.308
Abstract:
The EVME bus controller which is a key component of the HIRFLCSR control system was improved . Besides reconfiguring the embedded Linux， a utility program was developed for data exchange between the controller and the database. The bus controller is based on ARM920T(ARM9) micro processor which is BGA packaged. The bus controller has the universal interface of VGA display， keyboard， and mouse. The backboard interface logic is programmed in an insystem configurable FPGA device. The bus can drive high current up to 64 mA， with the flexibility of the programmable signal definitions. All the improved performance helped the EVME bus controller play a crucial role in HIRFLCSR control system.
The EVME bus controller which is a key component of the HIRFLCSR control system was improved . Besides reconfiguring the embedded Linux， a utility program was developed for data exchange between the controller and the database. The bus controller is based on ARM920T(ARM9) micro processor which is BGA packaged. The bus controller has the universal interface of VGA display， keyboard， and mouse. The backboard interface logic is programmed in an insystem configurable FPGA device. The bus can drive high current up to 64 mA， with the flexibility of the programmable signal definitions. All the improved performance helped the EVME bus controller play a crucial role in HIRFLCSR control system.
2009, 26(4): 312-318.
doi: 10.11804/NuclPhysRev.26.04.312
Abstract:
236U is a longlived radionuclide with half life of 2.342(3)×107 a. The ratio of 236U/238U is about 10-14 in the natural Uranium. The origin and production of 236U in globe are introduced and estimated in this paper，respectively. The major applicationsion of 236U as a 100 million year neutron flux integrator，as a “fingerprint” for monitoring nuclear environment and nuclear activity，and as a tracer in geological studies are briefly summarized. The accelerator mass spectrometry(AMS) measurement of 236U in the world and the research on HI13 tandem accelerator at China Institute of Atomic Energy(CIAE) is also mentioned in this paper.
236U is a longlived radionuclide with half life of 2.342(3)×107 a. The ratio of 236U/238U is about 10-14 in the natural Uranium. The origin and production of 236U in globe are introduced and estimated in this paper，respectively. The major applicationsion of 236U as a 100 million year neutron flux integrator，as a “fingerprint” for monitoring nuclear environment and nuclear activity，and as a tracer in geological studies are briefly summarized. The accelerator mass spectrometry(AMS) measurement of 236U in the world and the research on HI13 tandem accelerator at China Institute of Atomic Energy(CIAE) is also mentioned in this paper.
2009, 26(4): 319-321.
doi: 10.11804/NuclPhysRev.26.04.319
Abstract:
In this study we present preliminary results from a new detector: a thick gaseous electron multiplier(GEM) with resistive electrodes. The resistive electrodes protect the detector and the frontend electronics from damage by occasional discharges. In different gas mixtures, we test Thick GEM with Resistive Electrodes(RETGEM) detector for the first time, including counting rate, energy resolution, effective gain, and discharge probability. The results can satisfy the basic demand of RETGEM detector design.
In this study we present preliminary results from a new detector: a thick gaseous electron multiplier(GEM) with resistive electrodes. The resistive electrodes protect the detector and the frontend electronics from damage by occasional discharges. In different gas mixtures, we test Thick GEM with Resistive Electrodes(RETGEM) detector for the first time, including counting rate, energy resolution, effective gain, and discharge probability. The results can satisfy the basic demand of RETGEM detector design.
2009, 26(4): 322-326.
doi: 10.11804/NuclPhysRev.26.04.322
Abstract:
In this paper, the possibility using micromegas(MicroMesh Gaseous Structure) as neutron detector in 14 MeV neutron computed tomography(CT) has been simulated. The results show that the micromegas neutron detector has high spatial resolution and is a good candidate for neutron radiography. The threedimensional images of plant roots in soil are successfully and clearly obtained by the 14 MeV neutron CT with micromegas as a neutron detector. In the present simulation, MCNP is employed for 14 MeV neutron transport in the sample and Matlab for the 3D photograph reconstruction.
In this paper, the possibility using micromegas(MicroMesh Gaseous Structure) as neutron detector in 14 MeV neutron computed tomography(CT) has been simulated. The results show that the micromegas neutron detector has high spatial resolution and is a good candidate for neutron radiography. The threedimensional images of plant roots in soil are successfully and clearly obtained by the 14 MeV neutron CT with micromegas as a neutron detector. In the present simulation, MCNP is employed for 14 MeV neutron transport in the sample and Matlab for the 3D photograph reconstruction.
2009, 26(4): 327-332.
doi: 10.11804/NuclPhysRev.26.04.327
Abstract:
Characteristics of electrodeposited uranium films of uranium ore water sample in ammonium sulphate was investigated in this work. The optimized electrodeposited conditions were as follows： electrolyte was ammonium sulphate of 0.8 M， and current density at the cathode was 0.6 A/cm2， electrolyte pH value was 2.5， the time of plating on the electrodeposition was 1 h. In this situation， the uniform， thin and adheresive films were produced by electrodeposition method. Two samples were made， one electrodeposition of pure uranyl nitrate， and another electrodeposition of uranium ore water sample after chemical separation. Characteristics of electrodeposited uranium films of uranium ore water sample after chemical separation was studied， making comparisons with electrodeposited films of uranyl nitrate. The analysis of film characteristics was done through infrared (IR) spectrum， scanning electron microscopy(SEM)， element analysis and α spectrum measurment. According to Fourier transform infrared spectra， the asymmetric stretching vibration band of uranyl group is around 887 cm-1. In addition， according to IR spectrum， we know that uranium exists mainly as the form of hydrated polymeric compound in the film. Electrodeposited uranium films also included many NH+4. Polymeric structures of variable composition were present in the electrodeposited samples， with the unit monomeric formula UO2(OH)2·xNH3·yH2O or UO2(OH)2-x·(ONH4)x·yH2O. Scanning electron microscopy shows that the two samples have similar surface characteristics and no cluster is observed. The samples were also measured by spectrometer equipped with Passivated Implanted Planar Silicon(PIPS) detector. From the α spectrum， we know that isotopes of uranium in the film are 238U and 234U. 235U is not found in the α spectrum. It also shows that the chemical separation process can isolate uranium from other interfering elements effectively， the result of chemical separation is very satisfactory and electrodeposited process is rather efficient. Source electrodeposited in ammonium sulphate through optimized conditions satisfies the need of highresolution α spectrum.
Characteristics of electrodeposited uranium films of uranium ore water sample in ammonium sulphate was investigated in this work. The optimized electrodeposited conditions were as follows： electrolyte was ammonium sulphate of 0.8 M， and current density at the cathode was 0.6 A/cm2， electrolyte pH value was 2.5， the time of plating on the electrodeposition was 1 h. In this situation， the uniform， thin and adheresive films were produced by electrodeposition method. Two samples were made， one electrodeposition of pure uranyl nitrate， and another electrodeposition of uranium ore water sample after chemical separation. Characteristics of electrodeposited uranium films of uranium ore water sample after chemical separation was studied， making comparisons with electrodeposited films of uranyl nitrate. The analysis of film characteristics was done through infrared (IR) spectrum， scanning electron microscopy(SEM)， element analysis and α spectrum measurment. According to Fourier transform infrared spectra， the asymmetric stretching vibration band of uranyl group is around 887 cm-1. In addition， according to IR spectrum， we know that uranium exists mainly as the form of hydrated polymeric compound in the film. Electrodeposited uranium films also included many NH+4. Polymeric structures of variable composition were present in the electrodeposited samples， with the unit monomeric formula UO2(OH)2·xNH3·yH2O or UO2(OH)2-x·(ONH4)x·yH2O. Scanning electron microscopy shows that the two samples have similar surface characteristics and no cluster is observed. The samples were also measured by spectrometer equipped with Passivated Implanted Planar Silicon(PIPS) detector. From the α spectrum， we know that isotopes of uranium in the film are 238U and 234U. 235U is not found in the α spectrum. It also shows that the chemical separation process can isolate uranium from other interfering elements effectively， the result of chemical separation is very satisfactory and electrodeposited process is rather efficient. Source electrodeposited in ammonium sulphate through optimized conditions satisfies the need of highresolution α spectrum.
2009, 26(4): 333-337.
doi: 10.11804/NuclPhysRev.26.04.333
Abstract:
The behavior of the metallic multilayers of Si/\[Fe(10 nm)/Nb(4 nm)/Fe(4 nm)/ Nb(4 nm)\]2/\[Fe(4 nm)/Nb(4 nm)\]4 under 2 MeV Xeion irradiation has been investigated by depth profile analysis of Auger electron spectroscopy， Xray diffraction and vibrating sample magnetometer. The obtained experimental results show that the intermixing between Fe and Nb layers occurs in the 1.0×1014 ions/cm2 irradiated multilayer sample which results in the formation of Nbbased and Febased FeNb solid solution. For the samples irradiated to fluence larger than 1.0×1014 ions/cm2， amorphisation is observed， and moreover， the layered structure of the multilayer samples is broken up completely for the samples under 1.0×1016 or 2.0×1016 ions/cm2 irradiation. Vibrating sample magnetometer measurement also reveals that the magnetization of the samples changes with the evolution of the structure of multilayers. Possible mechanism of the modification in Fe/Nb multilayers induced by Xeion irradiation is briefly discussed.
The behavior of the metallic multilayers of Si/\[Fe(10 nm)/Nb(4 nm)/Fe(4 nm)/ Nb(4 nm)\]2/\[Fe(4 nm)/Nb(4 nm)\]4 under 2 MeV Xeion irradiation has been investigated by depth profile analysis of Auger electron spectroscopy， Xray diffraction and vibrating sample magnetometer. The obtained experimental results show that the intermixing between Fe and Nb layers occurs in the 1.0×1014 ions/cm2 irradiated multilayer sample which results in the formation of Nbbased and Febased FeNb solid solution. For the samples irradiated to fluence larger than 1.0×1014 ions/cm2， amorphisation is observed， and moreover， the layered structure of the multilayer samples is broken up completely for the samples under 1.0×1016 or 2.0×1016 ions/cm2 irradiation. Vibrating sample magnetometer measurement also reveals that the magnetization of the samples changes with the evolution of the structure of multilayers. Possible mechanism of the modification in Fe/Nb multilayers induced by Xeion irradiation is briefly discussed.
2009, 26(4): 338-342.
doi: 10.11804/NuclPhysRev.26.04.338
Abstract:
With development of high energy heavy ion accelerator， it is possible to perform heavy ion irradiation experiments of pressurized materials in diamond anvil cells(DACs). It is a new research field. The results expected from irradiation experiments under high pressure will have impacts on several scientific fields such as materials science，geoscience，geochronology，and nuclear waste storage. In this paper， some of recent works in this field are presented and reviewed. Furthermore，the research plan of materials under high pressure based on HIRFL-CSR is introduced.
With development of high energy heavy ion accelerator， it is possible to perform heavy ion irradiation experiments of pressurized materials in diamond anvil cells(DACs). It is a new research field. The results expected from irradiation experiments under high pressure will have impacts on several scientific fields such as materials science，geoscience，geochronology，and nuclear waste storage. In this paper， some of recent works in this field are presented and reviewed. Furthermore，the research plan of materials under high pressure based on HIRFL-CSR is introduced.
2009, 26(4): 343-347.
doi: 10.11804/NuclPhysRev.26.04.343
Abstract:
We investigate the interaction characteristics and mechanism of electromagnetic radiation field and cerebral nervous system. When the electromagnetic radiation is nonionization lowfrequency electromagnetic field， the twostate physical system in the cytoskeletal microtubule (MT) can be quantized. The state of information bits in cerebral neurous system is described by density matrix, and the system dynamics equation is established and solved. It indicates that when the brain is exposed to nonionization lowfrequency electromagnetic field, the density matrix nonopposite angle element of cerebral nervous qubit will never be zero, its quantum coherence characteristic can keep well, and the brain function will also be not damaged.
We investigate the interaction characteristics and mechanism of electromagnetic radiation field and cerebral nervous system. When the electromagnetic radiation is nonionization lowfrequency electromagnetic field， the twostate physical system in the cytoskeletal microtubule (MT) can be quantized. The state of information bits in cerebral neurous system is described by density matrix, and the system dynamics equation is established and solved. It indicates that when the brain is exposed to nonionization lowfrequency electromagnetic field, the density matrix nonopposite angle element of cerebral nervous qubit will never be zero, its quantum coherence characteristic can keep well, and the brain function will also be not damaged.
2009, 26(4): 348-351.
doi: 10.11804/NuclPhysRev.26.04.348
Abstract:
For estimating the effect of low doses Xray continual irradiation to immunity system of mouse， BALB/c mice were continually irradiated to 1.03 Gy by X rays at a dose rate of 0.2 Gy/min in 13 d. At 24 or 48 h after irradiation， the immunocyte cycle and apoptosis were determined by flow cytometry， and the thymus and spleen weights were measured too. The results showed that the cycle of thymocyte were arrested in G2/M at 24 h， the number of peripheral blood lymphocytes and thymocytes in G0/G1 phase at 48 h was up and the percentage of apoptosis had a significance increase in both of time points； the cycle of spleen lymphocytes was delayed in G0/G1 at 24 h， in S phase at 48 h， the apoptosis had a significance decrase at 24 and 48 h； spleen index declined significantly at 48 h. The results suggested that low doses continual Xray wholebody irradiation could activate different cell cycle checkpoints， and result in some changes of apoptosis and some damages to immunocytes. The continual Xray irradiation affects the organs differently， it might provide experiment basis for radioprotection.
For estimating the effect of low doses Xray continual irradiation to immunity system of mouse， BALB/c mice were continually irradiated to 1.03 Gy by X rays at a dose rate of 0.2 Gy/min in 13 d. At 24 or 48 h after irradiation， the immunocyte cycle and apoptosis were determined by flow cytometry， and the thymus and spleen weights were measured too. The results showed that the cycle of thymocyte were arrested in G2/M at 24 h， the number of peripheral blood lymphocytes and thymocytes in G0/G1 phase at 48 h was up and the percentage of apoptosis had a significance increase in both of time points； the cycle of spleen lymphocytes was delayed in G0/G1 at 24 h， in S phase at 48 h， the apoptosis had a significance decrase at 24 and 48 h； spleen index declined significantly at 48 h. The results suggested that low doses continual Xray wholebody irradiation could activate different cell cycle checkpoints， and result in some changes of apoptosis and some damages to immunocytes. The continual Xray irradiation affects the organs differently， it might provide experiment basis for radioprotection.
2009, 26(4): 352-355.
doi: 10.11804/NuclPhysRev.26.04.352
Abstract:
Lowenergy heavy ion implantation is an organism mutation method developed in middle of 1980s, which has a potential application in breeding and radiation therapy. The dosesurvival curve is a characteristic effect in radiobiology. Implanted with lowenergy heavy ions, organisms could manifest a Saddlelike dosesurvival curve. In this article, the Saddlelike dosesurvival effect and its modeling has been described, and several topics in model simulation are discussed.
Lowenergy heavy ion implantation is an organism mutation method developed in middle of 1980s, which has a potential application in breeding and radiation therapy. The dosesurvival curve is a characteristic effect in radiobiology. Implanted with lowenergy heavy ions, organisms could manifest a Saddlelike dosesurvival curve. In this article, the Saddlelike dosesurvival effect and its modeling has been described, and several topics in model simulation are discussed.
2009, 26(4): 356-359.
doi: 10.11804/NuclPhysRev.26.04.356
Abstract:
The chemical components of the body and glaze samples of some Ru porcelains from Yanhedian kiln and Jun official porcelains from Juntai kiln are determined by the technology of Energy Dispersive Xray Fluorescence(EDXRF) in this work. The difference of the two kiln’s glaze and body are analyzed by factor analysis method of Multidimensional statistical analysis. The results indicate that Yanhedian Ru porcelains can be well distinguished from Jun official porcelains from Juntai kiln. This evidence once again proves that Jun ceramics and Ru ceramics can be distinguished obviously.
The chemical components of the body and glaze samples of some Ru porcelains from Yanhedian kiln and Jun official porcelains from Juntai kiln are determined by the technology of Energy Dispersive Xray Fluorescence(EDXRF) in this work. The difference of the two kiln’s glaze and body are analyzed by factor analysis method of Multidimensional statistical analysis. The results indicate that Yanhedian Ru porcelains can be well distinguished from Jun official porcelains from Juntai kiln. This evidence once again proves that Jun ceramics and Ru ceramics can be distinguished obviously.
2009, 26(4): 360-366.
doi: 10.11804/NuclPhysRev.26.04.360
Abstract:
For reliable and consistent nuclear calculation, the cumulative yields for shortlived fission products are evaluated based on the available experimental data for 238U fission induced by fission spectrum neutrons and ~14 MeV neutrons. The data are processed using codes AVERAGE for weighed average and ZOOT for simultaneous evaluation. The evaluated data are compared with those in the major international nuclear data libraries, including ENDF/B-VII, JEF-2.2, JENDL-3.2 and CENDL-2. The present evaluation will be used to improve and update the CENDL-2 library.
For reliable and consistent nuclear calculation, the cumulative yields for shortlived fission products are evaluated based on the available experimental data for 238U fission induced by fission spectrum neutrons and ~14 MeV neutrons. The data are processed using codes AVERAGE for weighed average and ZOOT for simultaneous evaluation. The evaluated data are compared with those in the major international nuclear data libraries, including ENDF/B-VII, JEF-2.2, JENDL-3.2 and CENDL-2. The present evaluation will be used to improve and update the CENDL-2 library.
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