2004 Vol. 21, No. 1
Display Method:
2004, 21(1): 1-5.
doi: 10.11804/NuclPhysRev.21.01.001
Abstract:
We have extracted the probability for a valence particle being out the binding potential, as well as the rootmeansquare radius of the probability distribution from the measured nuclear asymptotic normalization coefficients. According to the criterion of nuclear halo, i.e., the valence particle has larger than 50% probability being out of the nuclear binding potential, a number of halo nuclei have been confirmed. Based on these results, we have obtained a very relaxed condition for nuclear halo formation. In addition, a number of nuclear halo candidates have been analyzed with the criteria of 〈r2〉/R2≥1.5 and 〈r2〉1/2/rc≥2.0. Furthermore, we present the scaling laws for the dimensionless quantity 〈r2〉/R2 of the nuclear halo in terms of an analytical expressions of the expectation value for the operator r2 in a finite squarewell potential.
We have extracted the probability for a valence particle being out the binding potential, as well as the rootmeansquare radius of the probability distribution from the measured nuclear asymptotic normalization coefficients. According to the criterion of nuclear halo, i.e., the valence particle has larger than 50% probability being out of the nuclear binding potential, a number of halo nuclei have been confirmed. Based on these results, we have obtained a very relaxed condition for nuclear halo formation. In addition, a number of nuclear halo candidates have been analyzed with the criteria of 〈r2〉/R2≥1.5 and 〈r2〉1/2/rc≥2.0. Furthermore, we present the scaling laws for the dimensionless quantity 〈r2〉/R2 of the nuclear halo in terms of an analytical expressions of the expectation value for the operator r2 in a finite squarewell potential.
2004, 21(1): 6-11.
doi: 10.11804/NuclPhysRev.21.01.006
Abstract:
Using modified surface delta interaction, enlarging the fp configuration space to include the 1g9/2 orbit with the abnormalparity, the deformed HartreeFock calculations for the eight nuclei: 64Ge, 66Ge, 68Ge, 70Se, 72Se , 74Se, 76Kr and 78Kr are performed. The groundstate and some particlehole excited configurations are obtained. The approximate angular momentum projected deformed HartreeFock (PDHF) method is applied to even even nuclei 64Ge and 74Se and oddA nuclus 79Kr. Both of their normal and abnormalparity bands are obtained. The calculated energy spectra are consistent well with experimental spectra.
Using modified surface delta interaction, enlarging the fp configuration space to include the 1g9/2 orbit with the abnormalparity, the deformed HartreeFock calculations for the eight nuclei: 64Ge, 66Ge, 68Ge, 70Se, 72Se , 74Se, 76Kr and 78Kr are performed. The groundstate and some particlehole excited configurations are obtained. The approximate angular momentum projected deformed HartreeFock (PDHF) method is applied to even even nuclei 64Ge and 74Se and oddA nuclus 79Kr. Both of their normal and abnormalparity bands are obtained. The calculated energy spectra are consistent well with experimental spectra.
2004, 21(1): 12-16.
doi: 10.11804/NuclPhysRev.21.01.012
Abstract:
The photon discrimination power of the ALICE photon spectrometer is simulated for incident particles n, p,π+, K+and γ with random energy distribution in the range from 0.5 to 100 GeV. The pricipale component analysis method is used to reduce the number of parameters in the shower shape analysis, and the results are compared with that from the seven parameter topology analysis.The efficiency dependence of purity for the photon discrimination is obtained for the deposited energy range 0.5—10, 10—20, 20—50 and 50—100 GeV.
The photon discrimination power of the ALICE photon spectrometer is simulated for incident particles n, p,π+, K+and γ with random energy distribution in the range from 0.5 to 100 GeV. The pricipale component analysis method is used to reduce the number of parameters in the shower shape analysis, and the results are compared with that from the seven parameter topology analysis.The efficiency dependence of purity for the photon discrimination is obtained for the deposited energy range 0.5—10, 10—20, 20—50 and 50—100 GeV.
2004, 21(1): 17-20.
doi: 10.11804/NuclPhysRev.21.01.017
Abstract:
he principle of the heavyion therapy is introduced in this article. In order to precisely determine the irradiation profiles and positions of scanned heavyion beams, we developed a large area parallel plate avalanche counter(PPAC). The detector consists of one anode, two cathodes and two windows with 250 mm×250 mm active area . It was measured at an anode voltage of 700 V and with flowing C3F8 gas at the pressure of 700 Pa. A position resolution of 0.54 mm by correction was obtained with an αsource. As compared with the similar devices, we consider the position resolution of the PPAC can satisfy the requirement of the facility of heavyion therapy.
he principle of the heavyion therapy is introduced in this article. In order to precisely determine the irradiation profiles and positions of scanned heavyion beams, we developed a large area parallel plate avalanche counter(PPAC). The detector consists of one anode, two cathodes and two windows with 250 mm×250 mm active area . It was measured at an anode voltage of 700 V and with flowing C3F8 gas at the pressure of 700 Pa. A position resolution of 0.54 mm by correction was obtained with an αsource. As compared with the similar devices, we consider the position resolution of the PPAC can satisfy the requirement of the facility of heavyion therapy.
2004, 21(1): 21-25.
doi: 10.11804/NuclPhysRev.21.01.021
Abstract:
The Compton backscattering polarimeter is described briefly on the basis of the principle of Compton backscattering in this paper. The polarization of the electron beam can be measured and monitored on time and nondestructively. The project will be one of applications of low energy γray beam of SLEGS.
The Compton backscattering polarimeter is described briefly on the basis of the principle of Compton backscattering in this paper. The polarization of the electron beam can be measured and monitored on time and nondestructively. The project will be one of applications of low energy γray beam of SLEGS.
2004, 21(1): 26-29.
doi: 10.11804/NuclPhysRev.21.01.026
Abstract:
To satisfy the requirements of HIRFL (Heavy Ion Research Facility in Lanzhou), series of experiments have been done to produce metallic ion beams. By now, numerous methods have been tested, in which MIVOC (Metallic Ion from Volatile Compounds), heating oven methods and plasma sputter methods are all included. According to the experiments, the results of using MIVOC methods and heating oven methods are very good. In most of our researches, emphasis was put upon the ion production of iron, Nickel, Tantanum, copper of different charge states. Among the ion beams we have obtained, 210 μA Fe11+, 175 μA Fe12+, 142 μA Fe13+, 25 μA Fe16+, 64 μA Ni10+, 57 μA Ni13+, 31 μA Ni15+ and 15 μA Ni16+ are representative results.
To satisfy the requirements of HIRFL (Heavy Ion Research Facility in Lanzhou), series of experiments have been done to produce metallic ion beams. By now, numerous methods have been tested, in which MIVOC (Metallic Ion from Volatile Compounds), heating oven methods and plasma sputter methods are all included. According to the experiments, the results of using MIVOC methods and heating oven methods are very good. In most of our researches, emphasis was put upon the ion production of iron, Nickel, Tantanum, copper of different charge states. Among the ion beams we have obtained, 210 μA Fe11+, 175 μA Fe12+, 142 μA Fe13+, 25 μA Fe16+, 64 μA Ni10+, 57 μA Ni13+, 31 μA Ni15+ and 15 μA Ni16+ are representative results.
2004, 21(1): 30-33.
doi: 10.11804/NuclPhysRev.21.01.030
Abstract:
he mass measurement of the nuclides far from the β stability by using Schottky mass spectrometry is an important aspect of the studies on HIRFLCSR. The principle of Schottky pickup and the method and prospect of Schottky mass spectrometry are also briefly analyzed. The Schottky pickup designed for the system of diagnostics and measurement of HIRFLCSR and also the test results are given.
he mass measurement of the nuclides far from the β stability by using Schottky mass spectrometry is an important aspect of the studies on HIRFLCSR. The principle of Schottky pickup and the method and prospect of Schottky mass spectrometry are also briefly analyzed. The Schottky pickup designed for the system of diagnostics and measurement of HIRFLCSR and also the test results are given.
2004, 21(1): 34-37.
doi: 10.11804/NuclPhysRev.21.01.034
Abstract:
The application of Fast High Voltage Transistor Switches (HTS) in pulsed ion beam and the time of flight(TOF ) setup is described. Secondary ion emissions from carbon nanotubes under bombardments of MeV Si and Si2 clusters are measured by using TOF. The measurements indicate that the yield of the secondary ion emissions of hydrogen increases with increasing energy of Si and it is attributed to the electronic processes. The yield of the secondary ions of hydrogen decreases with increasing energy of Si2 clusters and the enhancement of nuclear energy loss of cluster constituents at the surface of sample plays a more significant role in the secondary ion emission of hydrogen at the low energies.
The application of Fast High Voltage Transistor Switches (HTS) in pulsed ion beam and the time of flight(TOF ) setup is described. Secondary ion emissions from carbon nanotubes under bombardments of MeV Si and Si2 clusters are measured by using TOF. The measurements indicate that the yield of the secondary ion emissions of hydrogen increases with increasing energy of Si and it is attributed to the electronic processes. The yield of the secondary ions of hydrogen decreases with increasing energy of Si2 clusters and the enhancement of nuclear energy loss of cluster constituents at the surface of sample plays a more significant role in the secondary ion emission of hydrogen at the low energies.
2004, 21(1): 38-42.
doi: 10.11804/NuclPhysRev.21.01.038
Abstract:
We use the technique of wavelet analysis and epoch folding methods to search for the superimposed periodic signals of 1—10 TeV cosmic ray in the data obtained with Tibet Ⅱ/HD AS Array for April to June of 1998. Solar time semidiurnal and diurnal variations have been detected with about signalnoise ratio 10 and 6 for the 1 TeV and 10 TeV cosmic ray flux respectively. The semidiurnal variations are of an amplitude 0.3%, a phase 0.9 for 1 TeV cosmic ray and 0.4%, 0.9 for 10 TeV. The diurnal variations are of amplitude 0.5%, 0.7%, and phase 0.8 for 1 TeV and 10 TeV cosmic ray respectively.
We use the technique of wavelet analysis and epoch folding methods to search for the superimposed periodic signals of 1—10 TeV cosmic ray in the data obtained with Tibet Ⅱ/HD AS Array for April to June of 1998. Solar time semidiurnal and diurnal variations have been detected with about signalnoise ratio 10 and 6 for the 1 TeV and 10 TeV cosmic ray flux respectively. The semidiurnal variations are of an amplitude 0.3%, a phase 0.9 for 1 TeV cosmic ray and 0.4%, 0.9 for 10 TeV. The diurnal variations are of amplitude 0.5%, 0.7%, and phase 0.8 for 1 TeV and 10 TeV cosmic ray respectively.
2004, 21(1): 43-47.
doi: 10.11804/NuclPhysRev.21.01.043
Abstract:
Semicrystalline polyethylene terephthalate (PET) film stacks were irradiated with 22 MeV/u Fe ions at room temperature under vacuum. Ion beam induced microscopic structural modifications and amorphous transformation were investigated by means of Fourier transform infrared spectrosocopy (FTIR), ultraviolet visible absorption spectrosocopy (UV/Vis) and Xray diffractometer (XRD). It was found that irradiation induces bond breaking, formation of new free radiculs and amorphous transformation. These effects were found to depend on ion fluence , the electronic energy loss and aborbed dose. The creation of alkyne groups was found only at the aborbed dose higher than 5.0 MGy.
Semicrystalline polyethylene terephthalate (PET) film stacks were irradiated with 22 MeV/u Fe ions at room temperature under vacuum. Ion beam induced microscopic structural modifications and amorphous transformation were investigated by means of Fourier transform infrared spectrosocopy (FTIR), ultraviolet visible absorption spectrosocopy (UV/Vis) and Xray diffractometer (XRD). It was found that irradiation induces bond breaking, formation of new free radiculs and amorphous transformation. These effects were found to depend on ion fluence , the electronic energy loss and aborbed dose. The creation of alkyne groups was found only at the aborbed dose higher than 5.0 MGy.
2004, 21(1): 48-52.
doi: 10.11804/NuclPhysRev.21.01.048
Abstract:
Recent studies have indicated that biological effects, such as chromosomal aberration, gene mutation and cell death and so on, can be induced in cells that are not traversed by radiation directly. This phenomenon has been termed as bystander effects. In this paper, a few representative studies were reported and the possible mechanisms underlying the bystander effects were summarized. The reactive oxygen species (ROS) induced by ionizing radiation, cellular communication and some factors play important roles. Besides, the expression extent of bystander effects depended on radiation dose and quality were discussed. Bystander effects suggest that potential health risks associated with radiation exposure may be greater than those of original thought and this makes ultimate impact on human radiation risk assessment.
Recent studies have indicated that biological effects, such as chromosomal aberration, gene mutation and cell death and so on, can be induced in cells that are not traversed by radiation directly. This phenomenon has been termed as bystander effects. In this paper, a few representative studies were reported and the possible mechanisms underlying the bystander effects were summarized. The reactive oxygen species (ROS) induced by ionizing radiation, cellular communication and some factors play important roles. Besides, the expression extent of bystander effects depended on radiation dose and quality were discussed. Bystander effects suggest that potential health risks associated with radiation exposure may be greater than those of original thought and this makes ultimate impact on human radiation risk assessment.
2004, 21(1): 53-55.
doi: 10.11804/NuclPhysRev.21.01.053
Abstract:
To study the biological effectiveness in A172 glioma cells induced by γray irradiation, the survival fraction and the micronucleus frequency of A172 cells was measured. The result showed that the survival fraction was negatively correlated to the radiation dose. At 1.0 Gy, the micronucleus frequency peaked about (66.75±3.564)%, and the frequency of micronucleus cells peaked about (53.9 ±0.784 9)%. As the radiation dose increasing, the micronucleus frequency and the frequency of micronucleus cells decreased and finally kept steady about 42% and 37%, respectively.
To study the biological effectiveness in A172 glioma cells induced by γray irradiation, the survival fraction and the micronucleus frequency of A172 cells was measured. The result showed that the survival fraction was negatively correlated to the radiation dose. At 1.0 Gy, the micronucleus frequency peaked about (66.75±3.564)%, and the frequency of micronucleus cells peaked about (53.9 ±0.784 9)%. As the radiation dose increasing, the micronucleus frequency and the frequency of micronucleus cells decreased and finally kept steady about 42% and 37%, respectively.
2004, 21(1): 56-59.
doi: 10.11804/NuclPhysRev.21.01.056
Abstract:
The requirements of the screening method for high protein content in grain breeding are analysed. Methods for the determination of protein content in grain seed are reviewed.The principle and the advantages of the nuclear reaction method for the measurement of protein content in grain seed are discussed in detail.
The requirements of the screening method for high protein content in grain breeding are analysed. Methods for the determination of protein content in grain seed are reviewed.The principle and the advantages of the nuclear reaction method for the measurement of protein content in grain seed are discussed in detail.
2004, 21(1): 60-64.
doi: 10.11804/NuclPhysRev.21.01.060
Abstract:
The spectral properties of the planar channeling radiation of positron have been investigated by using Sinesquared Potential. At positron energy of 5 GeV a sharp line has been explained for the planar channeling radiation in Si(110 ). It is that theoretic results are compatible to the experiments.
The spectral properties of the planar channeling radiation of positron have been investigated by using Sinesquared Potential. At positron energy of 5 GeV a sharp line has been explained for the planar channeling radiation in Si(110 ). It is that theoretic results are compatible to the experiments.
2004, 21(1): 65-69.
doi: 10.11804/NuclPhysRev.21.01.065
Abstract:
We have calculated the energy levels of 3s3p3P1 for magnesiumlike sequence ions from KⅧ—TbLⅣ by HXR (HartreeForck plus statisticalexchange potential with relativistic corrections) method. With the important effects taken into account, we have made a systematic fit for the energy levels of the ions mentioned above. We predicted here the energy levels which have not been observed in experiments for ions from KⅧ to TbLⅣ.The wavelengths, oscillator strengths and probabilities of intercombination transitions 3s3p 3P1—3s21S0 are computed too.
We have calculated the energy levels of 3s3p3P1 for magnesiumlike sequence ions from KⅧ—TbLⅣ by HXR (HartreeForck plus statisticalexchange potential with relativistic corrections) method. With the important effects taken into account, we have made a systematic fit for the energy levels of the ions mentioned above. We predicted here the energy levels which have not been observed in experiments for ions from KⅧ to TbLⅣ.The wavelengths, oscillator strengths and probabilities of intercombination transitions 3s3p 3P1—3s21S0 are computed too.
2004, 21(1): 70-72.
doi: 10.11804/NuclPhysRev.21.01.070
Abstract:
In order to investigate the effect of minior actinide data on integral parameter, the acceleratordriven minior actinide benchmark system was selected in this work. The library based on ENDF/BVI.2 was used for the reference calculation. The sensitivities were examined by exchanging the minior actinides of CENDL3.0 and JENDL3.2 one after another. The Keff values and reaction rates were calculated. According to the comparisons, the difference in Keff from the refrence is more than 3‰, and the fission reaction rate of 242Am is about 15% lower than those of reference results. The elastic scattering reaction rate of 238Pu of CENDL3.0 is about 10% larger than those of ENDF/BVI.
In order to investigate the effect of minior actinide data on integral parameter, the acceleratordriven minior actinide benchmark system was selected in this work. The library based on ENDF/BVI.2 was used for the reference calculation. The sensitivities were examined by exchanging the minior actinides of CENDL3.0 and JENDL3.2 one after another. The Keff values and reaction rates were calculated. According to the comparisons, the difference in Keff from the refrence is more than 3‰, and the fission reaction rate of 242Am is about 15% lower than those of reference results. The elastic scattering reaction rate of 238Pu of CENDL3.0 is about 10% larger than those of ENDF/BVI.