2008 Vol. 25, No. 1
Display Method:
2008, 25(1): 1-7.
doi: 10.11804/NuclPhysRev.25.01.001
Abstract:
In terms of the angular dispersion plot of ln(dσ/dθ) versus θ2, which can be obtained from the angular distribution of the elastic scattering differential cross sections in heavy ion collisions, systematic analysis on the angular dispersions is made by using classical deflection function for the available experimental data on the target of 208Pb. Our systematic analyses bring about some important results. Firstly, there is an angular dispersion turning angle at forward angular range beyond the grazing angle. Secondly, the nuclear rainbow angle for such reaction systems can be determined by measuring differential cross sections of elastic scattering at forward angular range and analyzing the angular dispersion. Thirdly, analysis of angular dispersion may provide a way to determine a set of optical potential parameters by means of fitting the experimental data of elastic scattering differential cross sections. Finally, for the halo nuclei as the projectiles, there is an exotic behaviour, i. e., smaller angular dispersion turning angle.
In terms of the angular dispersion plot of ln(dσ/dθ) versus θ2, which can be obtained from the angular distribution of the elastic scattering differential cross sections in heavy ion collisions, systematic analysis on the angular dispersions is made by using classical deflection function for the available experimental data on the target of 208Pb. Our systematic analyses bring about some important results. Firstly, there is an angular dispersion turning angle at forward angular range beyond the grazing angle. Secondly, the nuclear rainbow angle for such reaction systems can be determined by measuring differential cross sections of elastic scattering at forward angular range and analyzing the angular dispersion. Thirdly, analysis of angular dispersion may provide a way to determine a set of optical potential parameters by means of fitting the experimental data of elastic scattering differential cross sections. Finally, for the halo nuclei as the projectiles, there is an exotic behaviour, i. e., smaller angular dispersion turning angle.
2008, 25(1): 8-14.
doi: 10.11804/NuclPhysRev.25.01.008
Abstract:
Based on the isospin and momentum dependent quantum molecular dynamics, we use the comparison for the differences between observables in the reactions induced by the halo\|neutron projectile and stable projectile with the same mass under complete same incident channel condition to protrude the isospin effect of halo\|neutron projectile and strengthen the sensitivity of observable on the isospin for extracting the information for the equation of state. For example, the halo\|neutron projectile increases the emitted neutron\|proton ratio and then enhances its sensitivity on the symmetrical potential. Two points above are more favorable than the normal neutron\|rich and neutron\|poor projectiles for extracting the symmetry potential. We also found that the neutron\|halo projectile induces the decrease of nuclear stopping in lower beam energy region and the increase in higher beam energy region, compared to corresponding same mass stable projectile under the same incident channel condition, so that we can use these properties to extract the information for the medium effect and isospin effect of in\|medium nucleon\|nucleon cross section.
Based on the isospin and momentum dependent quantum molecular dynamics, we use the comparison for the differences between observables in the reactions induced by the halo\|neutron projectile and stable projectile with the same mass under complete same incident channel condition to protrude the isospin effect of halo\|neutron projectile and strengthen the sensitivity of observable on the isospin for extracting the information for the equation of state. For example, the halo\|neutron projectile increases the emitted neutron\|proton ratio and then enhances its sensitivity on the symmetrical potential. Two points above are more favorable than the normal neutron\|rich and neutron\|poor projectiles for extracting the symmetry potential. We also found that the neutron\|halo projectile induces the decrease of nuclear stopping in lower beam energy region and the increase in higher beam energy region, compared to corresponding same mass stable projectile under the same incident channel condition, so that we can use these properties to extract the information for the medium effect and isospin effect of in\|medium nucleon\|nucleon cross section.
2008, 25(1): 15-19.
doi: 10.11804/NuclPhysRev.25.01.015
Abstract:
The shape phase transition between spherical U（5）and axially SU（3）deformed nuclei is investigated systemically for N=60 isotonic chain by the constrained relativistic mean|field theory with the interactions NL3 and PK1. The values of bind energy and quadruple deformation β2 are calculated and a good agreement is obtained as compared with the experiments. By examining the potential energy curve and single particle spectra obtained with this microscopic approach, the possible critical point nuclei with the structure of shape phase transition are suggested to be 114Xe and 116Ba, which is favored by the experiments.
The shape phase transition between spherical U（5）and axially SU（3）deformed nuclei is investigated systemically for N=60 isotonic chain by the constrained relativistic mean|field theory with the interactions NL3 and PK1. The values of bind energy and quadruple deformation β2 are calculated and a good agreement is obtained as compared with the experiments. By examining the potential energy curve and single particle spectra obtained with this microscopic approach, the possible critical point nuclei with the structure of shape phase transition are suggested to be 114Xe and 116Ba, which is favored by the experiments.
2008, 25(1): 20-26.
doi: 10.11804/NuclPhysRev.25.01.020
Abstract:
By using the gauge potential decomposition, we have discussed the selfdual equation and its solution in JackiwPi model. We obtained a new concrete selfdual equation and find relationship between ChernSimons vortex solution and topological number which is determined by Hopf indices and Brouwer degrees of mapping. To show the meaning of topological number we presented several figures with different topological numbers. In order to investigate the topological properties of many vortices, 5 parameters (two positions, one scale, one phase per vortex and one charge of each vortex) have been used to describe each vortex in many vortices solution in JackiwPi model. For many vortices, three figures with different topological numbers have been drown to show the effect of the charge on the many vortices solution. We also studied the quantization of flux of those vortices related to the topological numbers in this case.
By using the gauge potential decomposition, we have discussed the selfdual equation and its solution in JackiwPi model. We obtained a new concrete selfdual equation and find relationship between ChernSimons vortex solution and topological number which is determined by Hopf indices and Brouwer degrees of mapping. To show the meaning of topological number we presented several figures with different topological numbers. In order to investigate the topological properties of many vortices, 5 parameters (two positions, one scale, one phase per vortex and one charge of each vortex) have been used to describe each vortex in many vortices solution in JackiwPi model. For many vortices, three figures with different topological numbers have been drown to show the effect of the charge on the many vortices solution. We also studied the quantization of flux of those vortices related to the topological numbers in this case.
2008, 25(1): 27-30.
doi: 10.11804/NuclPhysRev.25.01.027
Abstract:
Based on the parameterized fully dressed quark propagator, we study the momentum dependence of the nucleon static properties and mean squared radius of nucleon in QCD. Our predicted values of nucleonic magnetic moment and charge electronic radius are consistent with empirical values used widely in literature and other calculations in the QCD inspired models. Our results show that the two physics quantities are not constants as one understood usually but they are running dynamical quantities. That is, for different momentum p2 they have different values. The calculating results also clearly show that the parameterized quark propagator is valid and reliable in practiced calculations.
Based on the parameterized fully dressed quark propagator, we study the momentum dependence of the nucleon static properties and mean squared radius of nucleon in QCD. Our predicted values of nucleonic magnetic moment and charge electronic radius are consistent with empirical values used widely in literature and other calculations in the QCD inspired models. Our results show that the two physics quantities are not constants as one understood usually but they are running dynamical quantities. That is, for different momentum p2 they have different values. The calculating results also clearly show that the parameterized quark propagator is valid and reliable in practiced calculations.
2008, 25(1): 31-37.
doi: 10.11804/NuclPhysRev.25.01.031
Abstract:
The recently detection outcome about interstellar 26Al is introduced, as well as the investigation progresses of interstellar 26Al nucleosynthesis in all models are reviewed. Finally, the new nuclear physics experimental results for the14N(p,γ) 15O reaction effect on sources of interstellar 26Al and an alternative new way for nucleosynthesis 26Al in SNIa are discussed.
The recently detection outcome about interstellar 26Al is introduced, as well as the investigation progresses of interstellar 26Al nucleosynthesis in all models are reviewed. Finally, the new nuclear physics experimental results for the14N(p,γ) 15O reaction effect on sources of interstellar 26Al and an alternative new way for nucleosynthesis 26Al in SNIa are discussed.
2008, 25(1): 38-43.
doi: 10.11804/NuclPhysRev.25.01.038
Abstract:
The Meteorological effects on “Scaler mode” secondary cosmic ray counts were discussed for the Sino\|Italian cooperated experiment ARGO\|YBJ in the Tibet Autonomous Region of China. The partial correlation coefficients were calculated between the counts and some environmental variables, such as the atmospheric air pressure, the temperature outside and inside the experimental hall, the atmospheric electric field and the humidity inside the hall. The results showed that there was a strong negative correlation between the counting rate of secondary cosmic ray and the atmospheric air pressure, and a moderate correlation was seen between the counts and the temperature outside of the hall. On the other hand, the atmospheric electric field had no correlation with the counts. The temperature inside the hall had an important influence on the secondary cosmic ray counts at low multiplicity (n=1) and the humidity inside the hall also had some influence. The larger the multiplicity, the less was the importance of the temperature and the humidity inside the hall. The data
of “Scaler mode” counts has been corrected by taking into account its linear correlation with the multiple meteorological parameters. This correction was reliable and important for further physics analysis.
The Meteorological effects on “Scaler mode” secondary cosmic ray counts were discussed for the Sino\|Italian cooperated experiment ARGO\|YBJ in the Tibet Autonomous Region of China. The partial correlation coefficients were calculated between the counts and some environmental variables, such as the atmospheric air pressure, the temperature outside and inside the experimental hall, the atmospheric electric field and the humidity inside the hall. The results showed that there was a strong negative correlation between the counting rate of secondary cosmic ray and the atmospheric air pressure, and a moderate correlation was seen between the counts and the temperature outside of the hall. On the other hand, the atmospheric electric field had no correlation with the counts. The temperature inside the hall had an important influence on the secondary cosmic ray counts at low multiplicity (n=1) and the humidity inside the hall also had some influence. The larger the multiplicity, the less was the importance of the temperature and the humidity inside the hall. The data
of “Scaler mode” counts has been corrected by taking into account its linear correlation with the multiple meteorological parameters. This correction was reliable and important for further physics analysis.
2008, 25(1): 44-47.
doi: 10.11804/NuclPhysRev.25.01.044
Abstract:
The requirement of the buffer gas in a RFQ (Radiofrequency Quadrupole) cooler and buncher has been introduced briefly. The pressure rise rate of RFQ1L has been studied theoretically and experimentally in detail. It shows that the pressure rise rate of RFQ1L is mainly due to the outgassing of the different materials in the vacuum chamber. The experiments indicated that the pressure rise rate of RFQ1L was (0.04±0.02) Pa/h.
The requirement of the buffer gas in a RFQ (Radiofrequency Quadrupole) cooler and buncher has been introduced briefly. The pressure rise rate of RFQ1L has been studied theoretically and experimentally in detail. It shows that the pressure rise rate of RFQ1L is mainly due to the outgassing of the different materials in the vacuum chamber. The experiments indicated that the pressure rise rate of RFQ1L was (0.04±0.02) Pa/h.
2008, 25(1): 48-51.
doi: 10.11804/NuclPhysRev.25.01.048
Abstract:
MCNP is a generalpurpose Monte Carlo NParticle code that can be used for neutron, photon, electron or coupled neutron/photon/electron transport, and it is widely accepted and used in many fields for its features of flexibility, generality and powerful functionality. However, MCNP shows some weakness in some aspects due to its professionusing. In this paper, both the procedure of MCNP development and its tendency are expounded, while the author’s point of view on MCNP code is put forward.
MCNP is a generalpurpose Monte Carlo NParticle code that can be used for neutron, photon, electron or coupled neutron/photon/electron transport, and it is widely accepted and used in many fields for its features of flexibility, generality and powerful functionality. However, MCNP shows some weakness in some aspects due to its professionusing. In this paper, both the procedure of MCNP development and its tendency are expounded, while the author’s point of view on MCNP code is put forward.
2008, 25(1): 52-55.
doi: 10.11804/NuclPhysRev.25.01.052
Abstract:
A two dimensional position sensitive CsI(Tl) scintillation detector readout with PSPMT was introduced. The performance of detector was simulated by using Monte Carlo code GEANT4. The position spectrum of RIB 17N and the detector’s position resolution were obtained, and the simulation results accorded with the experimental ones. The main factors， which can affect performance of the detector, and some planned detector improvements were presented.
A two dimensional position sensitive CsI(Tl) scintillation detector readout with PSPMT was introduced. The performance of detector was simulated by using Monte Carlo code GEANT4. The position spectrum of RIB 17N and the detector’s position resolution were obtained, and the simulation results accorded with the experimental ones. The main factors， which can affect performance of the detector, and some planned detector improvements were presented.
2008, 25(1): 56-60.
doi: 10.11804/NuclPhysRev.25.01.056
Abstract:
Study on the chemical properties of Super Heavy Elements (SHE) is one of the most important research aspects in nuclear chemistry. In order to study the chemical properties of SHE (Rf and Db), we can use the heavy ion beam of 22Ne to bombard the thick targets of Sm and Eu to prepare the isotopes of Hf and Ta and then do model experiments. Therefore, preparation of uniform, stable and thick targets of Sm and Eu is the key for the research. In this paper, the preparation process of thick targets of Sm and Eu from the isopropyl alcohol and nitric acid system was studied by using one cycle molecular plating method. Under the conditions that the current density was 3.8 mA/cm2, the distance between the two poles was 3 cm and the deposition lasted 1 h, the best results that the deposition yield was above 95% and the thickness of Sm and Eu targets was 1.6 and 1.5 mg/cm2 respectively which were determined by spectrophotometry were obtained.
Study on the chemical properties of Super Heavy Elements (SHE) is one of the most important research aspects in nuclear chemistry. In order to study the chemical properties of SHE (Rf and Db), we can use the heavy ion beam of 22Ne to bombard the thick targets of Sm and Eu to prepare the isotopes of Hf and Ta and then do model experiments. Therefore, preparation of uniform, stable and thick targets of Sm and Eu is the key for the research. In this paper, the preparation process of thick targets of Sm and Eu from the isopropyl alcohol and nitric acid system was studied by using one cycle molecular plating method. Under the conditions that the current density was 3.8 mA/cm2, the distance between the two poles was 3 cm and the deposition lasted 1 h, the best results that the deposition yield was above 95% and the thickness of Sm and Eu targets was 1.6 and 1.5 mg/cm2 respectively which were determined by spectrophotometry were obtained.
2008, 25(1): 61-66.
doi: 10.11804/NuclPhysRev.25.01.061
Abstract:
A microbeam X\|ray fluorescence(MXRF) analysis by employing X\|ray lens is used to determine the content of heavy metal elements and sulphur of pine needles from different regions of Beijing city, and the relationship between content and air pollution is studied. The elements leading to air pollution are confirmed, according to the comparation of injured needle with normal one. Two dimensional micro automatic scanning of middle part of Buxus microphylla foliages is achieved, and the results show the anti\|contaminated ability of Buxus microphylla foliages for several metal elements. The research validates the application of microbeam X\|ray fluorescence analysis by employing X\|ray lens in detecting envorinmental samples methodologically, which provides scientific basis for environmental research, pollution treatment and environmental management.
A microbeam X\|ray fluorescence(MXRF) analysis by employing X\|ray lens is used to determine the content of heavy metal elements and sulphur of pine needles from different regions of Beijing city, and the relationship between content and air pollution is studied. The elements leading to air pollution are confirmed, according to the comparation of injured needle with normal one. Two dimensional micro automatic scanning of middle part of Buxus microphylla foliages is achieved, and the results show the anti\|contaminated ability of Buxus microphylla foliages for several metal elements. The research validates the application of microbeam X\|ray fluorescence analysis by employing X\|ray lens in detecting envorinmental samples methodologically, which provides scientific basis for environmental research, pollution treatment and environmental management.
2008, 25(1): 67-71.
doi: 10.11804/NuclPhysRev.25.01.067
Abstract:
Human hepatocyte L02 cells were irradiated by the carbon ion beam with LET of 30 keV/μm and DNA strand breaks were detected immediately after the irradiation using comet assay. Based on the comet images, all the indexes of comet assay including head DNA%, tail DNA％, comet length, tail length, tail moment and olive tail moment were analyzed with CASP and SPSS 11.5 code. Statistically significant dose\|effect relationships could be observed in all the indexes of comet assay and TM increased with increasing the radiation dose. These experimental results suggest that carbon ion beam with intermediate LET value would cause remarkable DNA strand breaks immediately and the damage increases in a dose\|dependent manner. This work provides basic data and evidence for the risk assessment of heavy ion radiation to healthy tissue.
Human hepatocyte L02 cells were irradiated by the carbon ion beam with LET of 30 keV/μm and DNA strand breaks were detected immediately after the irradiation using comet assay. Based on the comet images, all the indexes of comet assay including head DNA%, tail DNA％, comet length, tail length, tail moment and olive tail moment were analyzed with CASP and SPSS 11.5 code. Statistically significant dose\|effect relationships could be observed in all the indexes of comet assay and TM increased with increasing the radiation dose. These experimental results suggest that carbon ion beam with intermediate LET value would cause remarkable DNA strand breaks immediately and the damage increases in a dose\|dependent manner. This work provides basic data and evidence for the risk assessment of heavy ion radiation to healthy tissue.
2008, 25(1): 72-76.
doi: 10.11804/NuclPhysRev.25.01.072
Abstract:
To provide basic data for heavyion cancer therapy， the biological effects of ionizing radiations with different linear energy transfers (LET) on radiosensitivity， cell cycle alteration and cell early apoptosis in H1299 cells were studied. The cell radiosensitivity was assessed by means of the standard colonyforming assay. The experimental results show that the survival fraction of H1299 cells irradiated with the 12C ions is evidently lower than that in the case of the Xrays. Moreover， compared with the Xrays the G2/M phase arrest and delay degree and the early apoptosis percentage in H1299 cells irradiated with the 12C ions were more prominent with increasing the radiation dose and repairing time. These results suggested that H1299 cells were more sensitive to 12C ion beam than Xrays. Moreover, less dose， few fractionation and longer fractionation interval were applicable to heavy ion therapy for p53 nulltype tumors.
To provide basic data for heavyion cancer therapy， the biological effects of ionizing radiations with different linear energy transfers (LET) on radiosensitivity， cell cycle alteration and cell early apoptosis in H1299 cells were studied. The cell radiosensitivity was assessed by means of the standard colonyforming assay. The experimental results show that the survival fraction of H1299 cells irradiated with the 12C ions is evidently lower than that in the case of the Xrays. Moreover， compared with the Xrays the G2/M phase arrest and delay degree and the early apoptosis percentage in H1299 cells irradiated with the 12C ions were more prominent with increasing the radiation dose and repairing time. These results suggested that H1299 cells were more sensitive to 12C ion beam than Xrays. Moreover, less dose， few fractionation and longer fractionation interval were applicable to heavy ion therapy for p53 nulltype tumors.
2008, 25(1): 77-81.
doi: 10.11804/NuclPhysRev.25.01.077
Abstract:
Gene chip technology is a molecular biology technique based on the theory of the hybridization sequencing, it has been applied in many biology fields. In this paper, a new therapy model which combined gene chip with radiotherapy is introduced. And it will be used as guideline in prophase, metaphase and anaphase of radiotherapy with heavy ion.
Gene chip technology is a molecular biology technique based on the theory of the hybridization sequencing, it has been applied in many biology fields. In this paper, a new therapy model which combined gene chip with radiotherapy is introduced. And it will be used as guideline in prophase, metaphase and anaphase of radiotherapy with heavy ion.
2008, 25(1): 82-86.
doi: 10.11804/NuclPhysRev.25.01.082
Abstract:
The effects of relativistic small radial component on atomic photoionization cross sections have been studied within relativistic average selfconsistent field theory. Relativistic effects are relatively unimportant for low photon energy, along with a review of highenergy photoionization the relativistic effects are quite important. The effects of relativistic small radial component on photoionization process should show breakdown when the nuclear finitesize effects is taken into account. The compression of wavefunction into the space near nucleus is so strong in highly charged ions that the electronic radius greatly decreases, and the effects of relativistic small radial component on photoionization cross sections turn to stronger than ordinary atoms. Since relativistic effects are extremely sensitive to the behavior of small radial component, the results are in good agreement with relativistic effects on photoionization cross section.
The effects of relativistic small radial component on atomic photoionization cross sections have been studied within relativistic average selfconsistent field theory. Relativistic effects are relatively unimportant for low photon energy, along with a review of highenergy photoionization the relativistic effects are quite important. The effects of relativistic small radial component on photoionization process should show breakdown when the nuclear finitesize effects is taken into account. The compression of wavefunction into the space near nucleus is so strong in highly charged ions that the electronic radius greatly decreases, and the effects of relativistic small radial component on photoionization cross sections turn to stronger than ordinary atoms. Since relativistic effects are extremely sensitive to the behavior of small radial component, the results are in good agreement with relativistic effects on photoionization cross section.
2008, 25(1): 87-90.
doi: 10.11804/NuclPhysRev.25.01.087
Abstract:
The infrared absorption behavior of heliumimplanted spinel with annealing temperature was studied by Fourier transformed infrared (FTIR) spectroscopy. It was found that the absorbance peak at 626.4 cm-1 shifted to smaller wave numbers with the increase of implantation fluence, while on subsequent annealing the absorbance peak shifted back to larger wave numbers with the increase of annealing temperature. The shift of the peak at 626.4 cm-1 with Heimplantation/annealing is considered to be related with the trapping and release of helium atoms in lattice sites in the spinel crystal.
The infrared absorption behavior of heliumimplanted spinel with annealing temperature was studied by Fourier transformed infrared (FTIR) spectroscopy. It was found that the absorbance peak at 626.4 cm-1 shifted to smaller wave numbers with the increase of implantation fluence, while on subsequent annealing the absorbance peak shifted back to larger wave numbers with the increase of annealing temperature. The shift of the peak at 626.4 cm-1 with Heimplantation/annealing is considered to be related with the trapping and release of helium atoms in lattice sites in the spinel crystal.
2008, 25(1): 91-96.
doi: 10.11804/NuclPhysRev.25.01.091
Abstract:
The complete neutron data of n+46—50, natTi, including cross sections of all reactions, angular distributions, double differential cross sections between 10-5 eV—20 MeV, are evaluated by analyzing the experimental data and modifying theoretical results. And resonance parameters of mutilevel BreitWigner, which are offered in JEDNL3.3, are adopted into the new evaluated data sets. Meanwhile, all of evaluated values have been compared with existing experimental values and other evaluated results from JENDL3.3 and JEFF3.1.
The complete neutron data of n+46—50, natTi, including cross sections of all reactions, angular distributions, double differential cross sections between 10-5 eV—20 MeV, are evaluated by analyzing the experimental data and modifying theoretical results. And resonance parameters of mutilevel BreitWigner, which are offered in JEDNL3.3, are adopted into the new evaluated data sets. Meanwhile, all of evaluated values have been compared with existing experimental values and other evaluated results from JENDL3.3 and JEFF3.1.
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