2011 Vol. 28, No. 2
Display Method:
2011, 28(2): 135-141.
doi: 10.11804/NuclPhysRev.28.02.135
Abstract:
The impact of the tensor force on the properties of finite nuclei is discussed by analyzing the spinorbit splittings and the multipole giant resonances in nuclei. It is found that the tensor force do plays an important role in nuclear structure. The experimental isospin dependence of the spinorbit splitting is very well depicted when the tensor force is included. The tensor force has a larger
effect on the spin flip magnetic dipole states than on the natural parity isoscalar quadrupole(2+) states. By analyzing the modifications to the HartreeFock mean field induced by the tensor terms，and the specific features of the residual particlehole tensor interaction，we find that the tensor force gives an
attractive contribution to the particlehole matrix elements.
The impact of the tensor force on the properties of finite nuclei is discussed by analyzing the spinorbit splittings and the multipole giant resonances in nuclei. It is found that the tensor force do plays an important role in nuclear structure. The experimental isospin dependence of the spinorbit splitting is very well depicted when the tensor force is included. The tensor force has a larger
effect on the spin flip magnetic dipole states than on the natural parity isoscalar quadrupole(2+) states. By analyzing the modifications to the HartreeFock mean field induced by the tensor terms，and the specific features of the residual particlehole tensor interaction，we find that the tensor force gives an
attractive contribution to the particlehole matrix elements.
2011, 28(2): 142-156.
doi: 10.11804/NuclPhysRev.28.02.142
Abstract:
Based on one updated microscopic transport model Ultrarelativistic Quantum Molecular Dynamics (UrQMD) with modifications of both potentials and twobody scattering cross sections, quite a few interesting observables, such as yields, collective flows, the nuclear stopping, and the HBT twoparticle interferometry, are systematically investigated for heavy ion collisions within a large beam energy regime of five orders of magnitude (from SIS, AGS, SPS up to RHIC). It is shown that a consistent explanation can be received from both singleparticle and twoparticle related observables.
Based on one updated microscopic transport model Ultrarelativistic Quantum Molecular Dynamics (UrQMD) with modifications of both potentials and twobody scattering cross sections, quite a few interesting observables, such as yields, collective flows, the nuclear stopping, and the HBT twoparticle interferometry, are systematically investigated for heavy ion collisions within a large beam energy regime of five orders of magnitude (from SIS, AGS, SPS up to RHIC). It is shown that a consistent explanation can be received from both singleparticle and twoparticle related observables.
2011, 28(2): 157-161.
doi: 10.11804/NuclPhysRev.28.02.157
Abstract:
The level structures of O and F isotopes are investigated in the framework of the singleparticle potential model. The isospin effect on the sd level spacing in F isotopes is studied by introducing an isospindependent term in the depth of the WoodsSaxon potential. The theoretical results of RMS radii and spinparity values are in agreement with the experimental data. In particular, the level inversion between proton levels of 2s1/2 and 1d5/2 in 16F, 15F and 14F is reproduced. The global tendency of the s-d level spacing agrees with the observed fact. In addition, the study confirms the oneproton halo structure in 17F(2s1/2).
The level structures of O and F isotopes are investigated in the framework of the singleparticle potential model. The isospin effect on the sd level spacing in F isotopes is studied by introducing an isospindependent term in the depth of the WoodsSaxon potential. The theoretical results of RMS radii and spinparity values are in agreement with the experimental data. In particular, the level inversion between proton levels of 2s1/2 and 1d5/2 in 16F, 15F and 14F is reproduced. The global tendency of the s-d level spacing agrees with the observed fact. In addition, the study confirms the oneproton halo structure in 17F(2s1/2).
2011, 28(2): 162-167.
doi: 10.11804/NuclPhysRev.28.02.162
Abstract:
Hadron Physics Lanzhou Spectrometer (HPLUS) is designed for the study of hadron production and decay from nucleonnucleon interaction in the GeV region. The current formation of HPLUS and the particle identification methods
for three polar angle regions are discussed. The Pluto event generator is applied to simulate the primary reactions on HPLUS， concerning four issues as followed: the agreement on pp elastic scattering angular distribution between Pluto samples and experimental data; the acceptance of charged K mesons in the strangeness production channels for the forward region of HPLUS; the
dependence of the maximum energy of photons and the minimum vertex
angle of two photons on the polar angle; the influence on the mass spectrum of excited states of nucleon with large resonant width from different reconstruction methods. It is proved that the Pluto event generator satisfies the requirements of Monte Carlo simulation for HPLUS.
Hadron Physics Lanzhou Spectrometer (HPLUS) is designed for the study of hadron production and decay from nucleonnucleon interaction in the GeV region. The current formation of HPLUS and the particle identification methods
for three polar angle regions are discussed. The Pluto event generator is applied to simulate the primary reactions on HPLUS， concerning four issues as followed: the agreement on pp elastic scattering angular distribution between Pluto samples and experimental data; the acceptance of charged K mesons in the strangeness production channels for the forward region of HPLUS; the
dependence of the maximum energy of photons and the minimum vertex
angle of two photons on the polar angle; the influence on the mass spectrum of excited states of nucleon with large resonant width from different reconstruction methods. It is proved that the Pluto event generator satisfies the requirements of Monte Carlo simulation for HPLUS.
2011, 28(2): 168-172.
doi: 10.11804/NuclPhysRev.28.02.168
Abstract:
The large transverse momentum distribution of lepton pairs produced in heavy-ion collisions has been studied, making use of the perturbative QCD. The contribution of the twoparton production process into lepton pairs in AuAu collisions is calculated. Lepton pair production with the direct single photon process and the resolved single photon process are introduced. We believe that the photon processes are significant. The complete processes at large transverse momentum are included, and moreover, the effect of shadowing and isospin of nucleus are also considered in heavyion collisions. Dilepton signals to regard the background of QGP have a good correction.
The large transverse momentum distribution of lepton pairs produced in heavy-ion collisions has been studied, making use of the perturbative QCD. The contribution of the twoparton production process into lepton pairs in AuAu collisions is calculated. Lepton pair production with the direct single photon process and the resolved single photon process are introduced. We believe that the photon processes are significant. The complete processes at large transverse momentum are included, and moreover, the effect of shadowing and isospin of nucleus are also considered in heavyion collisions. Dilepton signals to regard the background of QGP have a good correction.
2011, 28(2): 173-178.
doi: 10.11804/NuclPhysRev.28.02.173
Abstract:
Transverse mass distributions of Λ, , and Ξ- produced in PbPb reactions at
40 and 158 AGeV are described by an expansive threefireball model. A transverse expansion is observed in our calculation. The calculated results, by the expansive threefireball model, are in agreement with the experimental data of NA49 Collaboration.
Transverse mass distributions of Λ, , and Ξ- produced in PbPb reactions at
40 and 158 AGeV are described by an expansive threefireball model. A transverse expansion is observed in our calculation. The calculated results, by the expansive threefireball model, are in agreement with the experimental data of NA49 Collaboration.
2011, 28(2): 179-184.
doi: 10.11804/NuclPhysRev.28.02.179
Abstract:
While detecting supernova neutrinos in the Daya Bay neutrino laboratory， several supernova neutrino effects need to be considered， including the supernova shock effects， the neutrino collective effects， the MikheyevSmirnovWolfenstein (MSW) effects， and the Earth matter effects. The phenomena of neutrino oscillation is affected by the above effects. Using some ratios of the event numbers of different supernova neutrinos， we propose some possible methods to identify the mass hierarchy and acquire information about the neutrino mixing angle θ13 and neutrino masses.
While detecting supernova neutrinos in the Daya Bay neutrino laboratory， several supernova neutrino effects need to be considered， including the supernova shock effects， the neutrino collective effects， the MikheyevSmirnovWolfenstein (MSW) effects， and the Earth matter effects. The phenomena of neutrino oscillation is affected by the above effects. Using some ratios of the event numbers of different supernova neutrinos， we propose some possible methods to identify the mass hierarchy and acquire information about the neutrino mixing angle θ13 and neutrino masses.
2011, 28(2): 185-190.
doi: 10.11804/NuclPhysRev.28.02.185
Abstract:
We have discussed vortices in the nonAbelian dual superconductor theory.
Based on the work of Cho et al.， the Hamiltonian and the equations of motion of nonAbelian model were discussed in details. The nonAbelian dual superconductor theory related to the restricted guage potential was underlined and solutions of Dtype and Ntype integer vortices were obtained. Comparing with the traditional Abelian dual superconductor theory， we found that the the equations of motion and solutions of vortices in two models are almost same， which indicates it is reasonable to study quark confinement based on the Abelian dual superconductor theory.
We have discussed vortices in the nonAbelian dual superconductor theory.
Based on the work of Cho et al.， the Hamiltonian and the equations of motion of nonAbelian model were discussed in details. The nonAbelian dual superconductor theory related to the restricted guage potential was underlined and solutions of Dtype and Ntype integer vortices were obtained. Comparing with the traditional Abelian dual superconductor theory， we found that the the equations of motion and solutions of vortices in two models are almost same， which indicates it is reasonable to study quark confinement based on the Abelian dual superconductor theory.
2011, 28(2): 191-194.
doi: 10.11804/NuclPhysRev.28.02.191
Abstract:
In the classical mechanics frame and small amplitude approximation, the longitudinal motion equation of the particle was reduced to the Mathieu equation based on the perturbed Hamiltonian. It was pointed out that there is a series of new resonance lines in quasiisochronous synchrotron by the perturbation. The boundary curve and the stop width for order instability zone one were derived by the method of perturbabtion. Also it was pointed that the system is at the critical point when the phase becomes equal to the phase of the instable point for the synchrotron after it crossed the stop band, and the critical condition of the high frequency voltage modulation was derived.
In the classical mechanics frame and small amplitude approximation, the longitudinal motion equation of the particle was reduced to the Mathieu equation based on the perturbed Hamiltonian. It was pointed out that there is a series of new resonance lines in quasiisochronous synchrotron by the perturbation. The boundary curve and the stop width for order instability zone one were derived by the method of perturbabtion. Also it was pointed that the system is at the critical point when the phase becomes equal to the phase of the instable point for the synchrotron after it crossed the stop band, and the critical condition of the high frequency voltage modulation was derived.
2011, 28(2): 195-199.
doi: 10.11804/NuclPhysRev.28.02.195
Abstract:
Neutron detection efficiency of LS301 fastneutron detector was calibrated by measuring the neutron energy spectrum of 252Cf source, which has a standard fission neutron spectrum. A low mass, fast ionization chamber is used as the fission fragments detector in the timeofflight(TOF) spectrometer and afforded the start signal of neutron flight. The stop signal was offered by the anode of LS301. A measured TOF spectrum was turned to the neutron energy spectrum which will be compared with the standard one. Consequently, the fastneutron detection efficiency of LS301 was obtained. Calibration procedures of experimental and data processing was given. Relative detection efficiencies were obtained separately for threshold settings of 0.5, 0.7, 1.0 and 1.6 MeV for neutron energies under 10 MeV. Experimental results accorded with theoretical efficiency curves which were calculated with the Monte Carlo code NEFF50.
Neutron detection efficiency of LS301 fastneutron detector was calibrated by measuring the neutron energy spectrum of 252Cf source, which has a standard fission neutron spectrum. A low mass, fast ionization chamber is used as the fission fragments detector in the timeofflight(TOF) spectrometer and afforded the start signal of neutron flight. The stop signal was offered by the anode of LS301. A measured TOF spectrum was turned to the neutron energy spectrum which will be compared with the standard one. Consequently, the fastneutron detection efficiency of LS301 was obtained. Calibration procedures of experimental and data processing was given. Relative detection efficiencies were obtained separately for threshold settings of 0.5, 0.7, 1.0 and 1.6 MeV for neutron energies under 10 MeV. Experimental results accorded with theoretical efficiency curves which were calculated with the Monte Carlo code NEFF50.
2011, 28(2): 200-203.
doi: 10.11804/NuclPhysRev.28.02.200
Abstract:
In this paper, the performances as well as the production procedure of the chargedparticle telescope systems consisting of Si(Au) surface barrier detector and Si(Li) detector with different thicknesses were introduced briefly. As an example, the density distributions of the protons and electrons in space detected by the telescope systems mounted on the Fengyun3 satellite (FY3A) were also presented.
In this paper, the performances as well as the production procedure of the chargedparticle telescope systems consisting of Si(Au) surface barrier detector and Si(Li) detector with different thicknesses were introduced briefly. As an example, the density distributions of the protons and electrons in space detected by the telescope systems mounted on the Fengyun3 satellite (FY3A) were also presented.
2011, 28(2): 204-208.
doi: 10.11804/NuclPhysRev.28.02.204
Abstract:
F6 and *F8 are two methods to calculate energy deposition of photon by MCNP program. If the dimension of grid is almost the same long as the range of secondary electron， the precision of *F8 is higher than that of F6， but the efficiency of F6 is greatly higher than that of *F8. This paper presents five techniques to increase the efficiency，namely: F6 is use to the model with grid dimension bigger than 10 ranges of secondary electron; combination of F6 and *F8; change the substeps of electron; turn off knock on electron; selfadaption cutoff secondary electron. The two techniques， combination of F6 and *F8，selfadaption cutoff secondary electron， can provide a good precision and efficiency.
F6 and *F8 are two methods to calculate energy deposition of photon by MCNP program. If the dimension of grid is almost the same long as the range of secondary electron， the precision of *F8 is higher than that of F6， but the efficiency of F6 is greatly higher than that of *F8. This paper presents five techniques to increase the efficiency，namely: F6 is use to the model with grid dimension bigger than 10 ranges of secondary electron; combination of F6 and *F8; change the substeps of electron; turn off knock on electron; selfadaption cutoff secondary electron. The two techniques， combination of F6 and *F8，selfadaption cutoff secondary electron， can provide a good precision and efficiency.
2011, 28(2): 209-214.
doi: 10.11804/NuclPhysRev.28.02.209
Abstract:
Raman spectroscopy was used to study the structure changes of 6HSiC single crystal implanted with 5 MeV Kr (Krypton) at room temperature and subsequently annealed at high temperature. The Raman spectrum of the implanted SiC displays not only Si—C bonds vibration peaks， but also homonuclear Si—Si and C—C bond vibration peaks. Si—C bond vibration peaks gradually strengthen with increasing temperature. When annealing at 1000 ℃， the peak intensity of Raman spectrum is close to that of virgin specimen. It is found that crystal Si—Si bond vibration peaks do not change when annealing， but amorphous Si—Si bond vibration peaks disappear with increasing annealing temperature. The Relative Raman Intensity (RRI) values decrease with increasing fluence and tend to saturate， but the saturation fluences is different for various anneal temperature. The RRI values increases with raising annealing temperature， which is more obvious in low implanted specimens. At the same time， the RRI values separate gradually with increasing temperature and this phenomenon is strengthened by annealing temperature.
Raman spectroscopy was used to study the structure changes of 6HSiC single crystal implanted with 5 MeV Kr (Krypton) at room temperature and subsequently annealed at high temperature. The Raman spectrum of the implanted SiC displays not only Si—C bonds vibration peaks， but also homonuclear Si—Si and C—C bond vibration peaks. Si—C bond vibration peaks gradually strengthen with increasing temperature. When annealing at 1000 ℃， the peak intensity of Raman spectrum is close to that of virgin specimen. It is found that crystal Si—Si bond vibration peaks do not change when annealing， but amorphous Si—Si bond vibration peaks disappear with increasing annealing temperature. The Relative Raman Intensity (RRI) values decrease with increasing fluence and tend to saturate， but the saturation fluences is different for various anneal temperature. The RRI values increases with raising annealing temperature， which is more obvious in low implanted specimens. At the same time， the RRI values separate gradually with increasing temperature and this phenomenon is strengthened by annealing temperature.
2011, 28(2): 215-218.
doi: 10.11804/NuclPhysRev.28.02.215
Abstract:
To define the optimum dose of heavy ion beams for selecting high productive strains， we should study mortality and mutation effects of Streptomyces kitasatoensis irradiated by heavy ion beams in diffe rent doses. In this research， spores of Streptomyces kitasatoensis were irradiated by heavy ion beams with different doses. And survival rate， mortality rate， positive mutation and negative mutation were analyzed statistically. The results showed that high mortality rate appeared from 5 Gy and then the mortality rate curve became gently. Compared the positive and negative mutations in different doses， highest positive mutation was obtained in 40 Gy， while the negative mutation was lower in this dose， and the survival rate was 0.92%. So we defined that optimum dose of heavy ions radiation for Streptomyces kitasatoensis selection was 40 Gy in this experiment.
To define the optimum dose of heavy ion beams for selecting high productive strains， we should study mortality and mutation effects of Streptomyces kitasatoensis irradiated by heavy ion beams in diffe rent doses. In this research， spores of Streptomyces kitasatoensis were irradiated by heavy ion beams with different doses. And survival rate， mortality rate， positive mutation and negative mutation were analyzed statistically. The results showed that high mortality rate appeared from 5 Gy and then the mortality rate curve became gently. Compared the positive and negative mutations in different doses， highest positive mutation was obtained in 40 Gy， while the negative mutation was lower in this dose， and the survival rate was 0.92%. So we defined that optimum dose of heavy ions radiation for Streptomyces kitasatoensis selection was 40 Gy in this experiment.
2011, 28(2): 219-224.
doi: 10.11804/NuclPhysRev.28.02.219
Abstract:
The seedlings of rice (xindao18) were exposed to UVB (10.08 kJ/(m2d1 )) irradiation following the pretreatment with three different implantation dosages of lowenergy N+ ions. Changes in the levels of the superoxide (POD)，superoxide dismutase (SOD)，catalase (CAT)， malondialdehyde (MDA)，glutathione (GSH) and soluble sugar were measured. The result showed that the UV-B irradiation on the seedlings of rice pretreated with lowenergy ions implantation could lead to increase activities in POD and SOD，and the maximum appeared on the dose of 2.0×1017 ions/cm2. Meanwhile，it made the content of GSH increased， and caused the activity of CAT and the content of MDA to be decreased. But there was no obvious change in soluble sugar. It was suggested that the rice pretreated by low energy ion implantation could enhance the antioxidation capacity and defensive ability when irradiated by UV-B， and the antioxidation system could be induced earlier than carbohydrate system. Therefore， the biological effects of UV-B irradiation on rice pretreated by low energy ion implantation were quite obvious.
The seedlings of rice (xindao18) were exposed to UVB (10.08 kJ/(m2d1 )) irradiation following the pretreatment with three different implantation dosages of lowenergy N+ ions. Changes in the levels of the superoxide (POD)，superoxide dismutase (SOD)，catalase (CAT)， malondialdehyde (MDA)，glutathione (GSH) and soluble sugar were measured. The result showed that the UV-B irradiation on the seedlings of rice pretreated with lowenergy ions implantation could lead to increase activities in POD and SOD，and the maximum appeared on the dose of 2.0×1017 ions/cm2. Meanwhile，it made the content of GSH increased， and caused the activity of CAT and the content of MDA to be decreased. But there was no obvious change in soluble sugar. It was suggested that the rice pretreated by low energy ion implantation could enhance the antioxidation capacity and defensive ability when irradiated by UV-B， and the antioxidation system could be induced earlier than carbohydrate system. Therefore， the biological effects of UV-B irradiation on rice pretreated by low energy ion implantation were quite obvious.
2011, 28(2): 225-229.
doi: 10.11804/NuclPhysRev.28.02.225
Abstract:
To study the trend of the changes of trace elements in serum of golden hamster with cheek pouch carcinoma after irradiation by heavy ion beam, the cheek pouch carcinoma of golden hamster was exposed to different doses of heavy ion beam， after 4 weeks, the contents of Cu, Zn, Fe, Mg and Ca in serum were detected by flame method of Atomic Absorption Spectrometer. The contents of Cu, Zn, Ca and Mg in experimental groups with cheek pouch carcinoma were significantly lower than that of the normal group (P<0.05). After irradiated by 0, 4, 6, 8, 12 Gy heavy ion beam, the 4 Gy group showed a tendency downward, when the irradiation dose reached 6 Gy, the contents of Fe, Zn were increased, and decreased at 12 Gy. While Cu, Ca and Mg content of 8 Gy group rose to the highest, and decreased at 12 Gy. All of the results showed a dosereaction relationship (P<0.05). The irradiation of heavy ion beam maybe significantly affect the content of trace elements in serum of golden hamster with cheek pouch carcinoma.
To study the trend of the changes of trace elements in serum of golden hamster with cheek pouch carcinoma after irradiation by heavy ion beam, the cheek pouch carcinoma of golden hamster was exposed to different doses of heavy ion beam， after 4 weeks, the contents of Cu, Zn, Fe, Mg and Ca in serum were detected by flame method of Atomic Absorption Spectrometer. The contents of Cu, Zn, Ca and Mg in experimental groups with cheek pouch carcinoma were significantly lower than that of the normal group (P<0.05). After irradiated by 0, 4, 6, 8, 12 Gy heavy ion beam, the 4 Gy group showed a tendency downward, when the irradiation dose reached 6 Gy, the contents of Fe, Zn were increased, and decreased at 12 Gy. While Cu, Ca and Mg content of 8 Gy group rose to the highest, and decreased at 12 Gy. All of the results showed a dosereaction relationship (P<0.05). The irradiation of heavy ion beam maybe significantly affect the content of trace elements in serum of golden hamster with cheek pouch carcinoma.
2011, 28(2): 230-235.
doi: 10.11804/NuclPhysRev.28.02.230
Abstract:
Radiationinduced bystander effect is defined as the induction of damage in neighboring nonhit cells by signals released from directlyirradiated cells. ROS， NO and cytokines are involved in signaling pathways of bystander effects. Recently， the bystander effects in vivo have been reported more and more. It has been indicated that radiation induced bystander effect was localized not only in bystander tissues but also in distant organs. This effect includes many biological endpoints such as DNA damage， epigenetic， miRNA and gene expression changes， cell proliferation and apoptosis. In this review we described different aspects of ionizing radiationinduced bystander effects such as its characteristics， sex specific， signaling transfer， dose and LET dependence， and related mechanisms.
Radiationinduced bystander effect is defined as the induction of damage in neighboring nonhit cells by signals released from directlyirradiated cells. ROS， NO and cytokines are involved in signaling pathways of bystander effects. Recently， the bystander effects in vivo have been reported more and more. It has been indicated that radiation induced bystander effect was localized not only in bystander tissues but also in distant organs. This effect includes many biological endpoints such as DNA damage， epigenetic， miRNA and gene expression changes， cell proliferation and apoptosis. In this review we described different aspects of ionizing radiationinduced bystander effects such as its characteristics， sex specific， signaling transfer， dose and LET dependence， and related mechanisms.
2011, 28(2): 236-240.
doi: 10.11804/NuclPhysRev.28.02.236
Abstract:
In this paper, we have addressed the problem of the radiation transport with the Monte Carlo Nparticle(MCNP) code. This is a generalpurpose Monte Carlo tool designed to transport neutron, photon and electron in three dimensional geometries. To examine the performance of MCNP5 code in the field of external radiotherapy, we performed the modeling of an Electron Density phantom (EDP) irradiated by photons from 60Co source. The model was used to calculate the Percent Depth Dose (PDD) at different depths in an EDP. One field size for PDD has been examined. A 60Co photons source placed at 80 cm source to surface distance (SSD). The results of calculations were compared to TPS data obtained at National Institute of Oncology of Rabat.
In this paper, we have addressed the problem of the radiation transport with the Monte Carlo Nparticle(MCNP) code. This is a generalpurpose Monte Carlo tool designed to transport neutron, photon and electron in three dimensional geometries. To examine the performance of MCNP5 code in the field of external radiotherapy, we performed the modeling of an Electron Density phantom (EDP) irradiated by photons from 60Co source. The model was used to calculate the Percent Depth Dose (PDD) at different depths in an EDP. One field size for PDD has been examined. A 60Co photons source placed at 80 cm source to surface distance (SSD). The results of calculations were compared to TPS data obtained at National Institute of Oncology of Rabat.
2011, 28(2): 241-244.
doi: 10.11804/NuclPhysRev.28.02.241
Abstract:
Using a Singlephotoncounting CCD, Xray emission spectra of high purity Mo irradiated by ultrashort and ultraintense laser pulse was firstly detected. The experiment was carried out with the SILEX1 laser facility. The experimental results show that, for Mo target, characteristic Kshell emission (Kα) is observed in the 0.23—2.32 J energy range in addition to a broadband bremsstrahlung background, and the Xray radiation intensity, thermal radiation and bremsstrahlung increase with enhancementofthe laser power density.
Using a Singlephotoncounting CCD, Xray emission spectra of high purity Mo irradiated by ultrashort and ultraintense laser pulse was firstly detected. The experiment was carried out with the SILEX1 laser facility. The experimental results show that, for Mo target, characteristic Kshell emission (Kα) is observed in the 0.23—2.32 J energy range in addition to a broadband bremsstrahlung background, and the Xray radiation intensity, thermal radiation and bremsstrahlung increase with enhancementofthe laser power density.
2011, 28(2): 245-250.
doi: 10.11804/NuclPhysRev.28.02.245
Abstract:
Based on multiconfiguration DiracFock method and the corresponding packages GRASP92 and RATIP, as well as the newly developed RELPHOTO08, the variations of M subshell photoionization cross sections with the photon energy, ionization degree and subshells for highly charged gold ions are studied systemically. The present results show that the cross sections are decreasing monotonously with the photon energy; for the photoionization of nl electrons, if the principal quantum number of removed electron is large enough, the cross sections are essentially unchanged upon the presence or absence of outer electrons; for same ionization degree, the angular quantum number introduces two opposite effects which could exist simultaneously, and the intricate variations of cross sections with the photon energy originate from the competition between these two different effects.
Based on multiconfiguration DiracFock method and the corresponding packages GRASP92 and RATIP, as well as the newly developed RELPHOTO08, the variations of M subshell photoionization cross sections with the photon energy, ionization degree and subshells for highly charged gold ions are studied systemically. The present results show that the cross sections are decreasing monotonously with the photon energy; for the photoionization of nl electrons, if the principal quantum number of removed electron is large enough, the cross sections are essentially unchanged upon the presence or absence of outer electrons; for same ionization degree, the angular quantum number introduces two opposite effects which could exist simultaneously, and the intricate variations of cross sections with the photon energy originate from the competition between these two different effects.
2011, 28(2): 251-255.
doi: 10.11804/NuclPhysRev.28.02.251
Abstract:
The excitation function of 15N（p, n)15O reaction at 0 degree was measured at 38 energy points using the fast neutron TimeofFlight (TOF) spectrometer at the HI13 Tandem Accelerator in the China Institute of Atomic Energy（CIAE）. The measured data were analyzed by MonteCarlo simulation for the corrections of neutron flux attenuation and uncertainty of the thickness of the entrance foil. Three resonance peaks were observed in this experiment in the energy range from 6.029 to 8.056 MeV，which is comparable with the DROSG2000 evaluated data and the PTB data. However，more experimental studies are needed since the cross sections deviate with each other.
The excitation function of 15N（p, n)15O reaction at 0 degree was measured at 38 energy points using the fast neutron TimeofFlight (TOF) spectrometer at the HI13 Tandem Accelerator in the China Institute of Atomic Energy（CIAE）. The measured data were analyzed by MonteCarlo simulation for the corrections of neutron flux attenuation and uncertainty of the thickness of the entrance foil. Three resonance peaks were observed in this experiment in the energy range from 6.029 to 8.056 MeV，which is comparable with the DROSG2000 evaluated data and the PTB data. However，more experimental studies are needed since the cross sections deviate with each other.
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