2010 Vol. 27, No. 4
Display Method:
2010, 27(4): 363-389.
doi: 10.11804/NuclPhysRev.27.04.363
Abstract:
By means of γ-γ-γ and γ-γ(θ) measurements of prompt fission γ rays from 252Cf using Gammasphere, new insights have been gained into the A~100 (Z~40, N>56) neutron rich region, which has long been of interest for shape transitions, shape coexistence and onset of deformations. The systematic investigations of odd-Z isotopes have revealed a shape transition from axially symmetric shapes with very large quadrupole deformations in Z=39 (Y) to near maximum triaxial shapes with moderate quadrupole deformations in Z=43 (Tc), 44 (Ru), 45 (Rh) isotopes. The Nb (Z=41) isotopes are found to be transitional with regard to this shape transition. The bandcrossings observed in the evenN Tc and Rh isotopes are attributed to alignment of a pair of h11/2neutrons. The longexpected sudden shape transition in Nb isotopic chain is now observed. The longsought highspin level scheme and deformed states in 100Nb (N=59) were identified. The ground state of 100Nb was found to be strongly deformed, in disagreement with existing theory. The shape coexistence was confirmed in the nucleus, and the sudden shape transition in the Nb isotopic chain was seen to occur between N=58 (spherical) to N=59 (strongly deformed), in contrast to the sudden shape transition from N=59 (spherical) toN=60 (strongly deformed) in Sr (Z=38), Y (Z=39) and Zr (Z=40) isotopic chains. The observation of strongly deformed ground state in 100Nb and its very large and irregular moments of inertia make 100Nb an especially interesting case for further theoretical studies.
Recent detailed studies of octupole excitations in odd-Z Cs (Z=55) and La (Z=57) isotopes have discovered a sharp drop in electric dipole moments D0 in the Cs isotopic chain 141, 143, 144Cs, and, most likely, the previously reported moderate drop in D0 in 145, 147La is extended sharply down in 148La. The sharp drops of D0 in Cs and La are most likely analogous to those reported in 146Ba and 224Ra, which were accounted for by the reflectionasymmetric mean field shell correction theory. The very large D0 in both 141Cs and 142Xe and the simplexdependent D0 deduced in 141Cs but not in 143Cs need further theoretical studies. Based on rotational frequency ratios, ω-(I)/ω+(I), octupole vibrations are proposed in Cs isotopes, like the cases in Xe isotopes, while octupole deformations are suggested in La isotopes.
By means of γ-γ-γ and γ-γ(θ) measurements of prompt fission γ rays from 252Cf using Gammasphere, new insights have been gained into the A~100 (Z~40, N>56) neutron rich region, which has long been of interest for shape transitions, shape coexistence and onset of deformations. The systematic investigations of odd-Z isotopes have revealed a shape transition from axially symmetric shapes with very large quadrupole deformations in Z=39 (Y) to near maximum triaxial shapes with moderate quadrupole deformations in Z=43 (Tc), 44 (Ru), 45 (Rh) isotopes. The Nb (Z=41) isotopes are found to be transitional with regard to this shape transition. The bandcrossings observed in the evenN Tc and Rh isotopes are attributed to alignment of a pair of h11/2neutrons. The longexpected sudden shape transition in Nb isotopic chain is now observed. The longsought highspin level scheme and deformed states in 100Nb (N=59) were identified. The ground state of 100Nb was found to be strongly deformed, in disagreement with existing theory. The shape coexistence was confirmed in the nucleus, and the sudden shape transition in the Nb isotopic chain was seen to occur between N=58 (spherical) to N=59 (strongly deformed), in contrast to the sudden shape transition from N=59 (spherical) toN=60 (strongly deformed) in Sr (Z=38), Y (Z=39) and Zr (Z=40) isotopic chains. The observation of strongly deformed ground state in 100Nb and its very large and irregular moments of inertia make 100Nb an especially interesting case for further theoretical studies.
Recent detailed studies of octupole excitations in odd-Z Cs (Z=55) and La (Z=57) isotopes have discovered a sharp drop in electric dipole moments D0 in the Cs isotopic chain 141, 143, 144Cs, and, most likely, the previously reported moderate drop in D0 in 145, 147La is extended sharply down in 148La. The sharp drops of D0 in Cs and La are most likely analogous to those reported in 146Ba and 224Ra, which were accounted for by the reflectionasymmetric mean field shell correction theory. The very large D0 in both 141Cs and 142Xe and the simplexdependent D0 deduced in 141Cs but not in 143Cs need further theoretical studies. Based on rotational frequency ratios, ω-(I)/ω+(I), octupole vibrations are proposed in Cs isotopes, like the cases in Xe isotopes, while octupole deformations are suggested in La isotopes.
2010, 27(4): 390-398.
doi: 10.11804/NuclPhysRev.27.04.390
Abstract:
The breakup and knockout reactions at intermediate and high energies are of the advantages such as simple reaction mechanism， sensitive to the surface of the nucleus， mature theoretical treatment and so on， and therefore have been applied successfully to the study of exotic structure of unstable nuclei. In order to deal with the problems of the secondary beam which often has large beam spot size and energy spread， the special experimental methods and techniques， such as inverse kinematics complete detection， combining light and heavy targets， high resolution dispersionmatch magnetic spectrometer， forward neutron spectrometer， inbeam γ spectroscopyetc， have been developed and applied over the time， allowing much improved detection capability and sensitivity. This report gives an overview of the progress made with the breakup and knockout reactions for unstable nuclei study， based essentially on the new physics explored and the evolution of the experimental method applied. Possible future developments are also discussed.
The breakup and knockout reactions at intermediate and high energies are of the advantages such as simple reaction mechanism， sensitive to the surface of the nucleus， mature theoretical treatment and so on， and therefore have been applied successfully to the study of exotic structure of unstable nuclei. In order to deal with the problems of the secondary beam which often has large beam spot size and energy spread， the special experimental methods and techniques， such as inverse kinematics complete detection， combining light and heavy targets， high resolution dispersionmatch magnetic spectrometer， forward neutron spectrometer， inbeam γ spectroscopyetc， have been developed and applied over the time， allowing much improved detection capability and sensitivity. This report gives an overview of the progress made with the breakup and knockout reactions for unstable nuclei study， based essentially on the new physics explored and the evolution of the experimental method applied. Possible future developments are also discussed.
2010, 27(4): 399-410.
doi: 10.11804/NuclPhysRev.27.04.399
Abstract:
nuclear structure; compressed finite nuclei; Δ-resonance; Hartree-Fock method; single particle energy
nuclear structure; compressed finite nuclei; Δ-resonance; Hartree-Fock method; single particle energy
2010, 27(4): 411-415.
doi: 10.11804/NuclPhysRev.27.04.411
Abstract:
Based on the continuum discretized coupled channels(CDCC) theory, and the hypothesis that the residual nucleus locates not only in bound state but also in a series of excited states, the contribution of deuteron breakup effect in outgoing proton energy spectra are studied in the present work. And the results can basically explain the experimental results that a peak structure is appeared in the outgoing proton energy spectra at about half of the incident energy. The results of present calculation generally agree with those obtained from C. Kalbach’s empirical formulaum.
Based on the continuum discretized coupled channels(CDCC) theory, and the hypothesis that the residual nucleus locates not only in bound state but also in a series of excited states, the contribution of deuteron breakup effect in outgoing proton energy spectra are studied in the present work. And the results can basically explain the experimental results that a peak structure is appeared in the outgoing proton energy spectra at about half of the incident energy. The results of present calculation generally agree with those obtained from C. Kalbach’s empirical formulaum.
2010, 27(4): 416-420.
doi: 10.11804/NuclPhysRev.27.04.416
Abstract:
The nucleus-nucleus cross sections(σNN) include the protonproton cross section，neutron-neutron cross section， and neutron-proton cross section. σNNchange with the variations of the incident energies and the densities. Some parameterizations of σNN as a function of incident energy and density have been proposed in the theoretical and experimental study of nuclear reactions. Through the calculation of reaction cross sections of 12C+12C at different energies, the effect of different σNN parameterizations in the reaction cross sections of 12 are studied.
The nucleus-nucleus cross sections(σNN) include the protonproton cross section，neutron-neutron cross section， and neutron-proton cross section. σNNchange with the variations of the incident energies and the densities. Some parameterizations of σNN as a function of incident energy and density have been proposed in the theoretical and experimental study of nuclear reactions. Through the calculation of reaction cross sections of 12C+12C at different energies, the effect of different σNN parameterizations in the reaction cross sections of 12 are studied.
2010, 27(4): 421-425.
doi: 10.11804/NuclPhysRev.27.04.421
Abstract:
Using Glauber model， we present the impact parameter dependences of the numbers of participants and binary nucleon-nucleon collisions in nucleus-nucleus collisions. Then， on the basis of this work，after considering the effect of energy loss of participants in their multiple collisions，we get the pseudorapidity distributions of charged-particles as a function of impact parameter in nucleus-nucleus collisions through weighted superposition of the distributions in effective binary nucleon-nucleon collisions. The experimental measurements carried out by RHIC PHOBOS Collaboration in different central Cu+Cu collisions at different energies were analyzed by using this model. The theoretical results are well consistent with the experimental observations
Using Glauber model， we present the impact parameter dependences of the numbers of participants and binary nucleon-nucleon collisions in nucleus-nucleus collisions. Then， on the basis of this work，after considering the effect of energy loss of participants in their multiple collisions，we get the pseudorapidity distributions of charged-particles as a function of impact parameter in nucleus-nucleus collisions through weighted superposition of the distributions in effective binary nucleon-nucleon collisions. The experimental measurements carried out by RHIC PHOBOS Collaboration in different central Cu+Cu collisions at different energies were analyzed by using this model. The theoretical results are well consistent with the experimental observations
2010, 27(4): 426-431.
doi: 10.11804/NuclPhysRev.27.04.426
Abstract:
The azimuthal anisotropy of high pT direct photons is investigated by using the coefficient of elliptic flow ν2 in non-central nucleus-nucleus collision at LHC energies. These photons come from radiation induced by the interaction between jet and hot/dense medium. The azimuthal anisotropy of high pT direct photons is investigated by using the coefficient of elliptic flow ν2 in non-central nucleus-nucleus collision at LHC energies. These photons come There is π/2 difference between direct photons and hadrons for the azimuthal elliptic flow ν2. Such photons are the main source of the negative part of ν2 for direct photons. The dependence of the direct photon ν2 on the transverse momentum pT at LHC energy is found to be consistent with the experimental results at RHIC energy. Furthermore, we find that the value of the direct photon ν2 at LHC energy is smaller than that at RHIC energy. The value of the transverse momentum at which the direct photon ν2 changes from negative value to positive at LHC is higher than that at RHIC. It’sfound the enhanced jetquenching effect and enhanced contribution for the elliptic flow ν2 of the direct photons emitted from surface at LHC energy.
The azimuthal anisotropy of high pT direct photons is investigated by using the coefficient of elliptic flow ν2 in non-central nucleus-nucleus collision at LHC energies. These photons come from radiation induced by the interaction between jet and hot/dense medium. The azimuthal anisotropy of high pT direct photons is investigated by using the coefficient of elliptic flow ν2 in non-central nucleus-nucleus collision at LHC energies. These photons come There is π/2 difference between direct photons and hadrons for the azimuthal elliptic flow ν2. Such photons are the main source of the negative part of ν2 for direct photons. The dependence of the direct photon ν2 on the transverse momentum pT at LHC energy is found to be consistent with the experimental results at RHIC energy. Furthermore, we find that the value of the direct photon ν2 at LHC energy is smaller than that at RHIC energy. The value of the transverse momentum at which the direct photon ν2 changes from negative value to positive at LHC is higher than that at RHIC. It’sfound the enhanced jetquenching effect and enhanced contribution for the elliptic flow ν2 of the direct photons emitted from surface at LHC energy.
2010, 27(4): 432-435.
doi: 10.11804/NuclPhysRev.27.04.432
Abstract:
The multi-component dual superconductor theory has been studied based on
the new parameterization of gauge potential. The selfdual vortices of the multicomponent GinzburgLandau model was investigated. Then we considered the wall vortex whose flux goes to infinity. At last, the relationship between the bag model and wall vortices is considered.
The multi-component dual superconductor theory has been studied based on
the new parameterization of gauge potential. The selfdual vortices of the multicomponent GinzburgLandau model was investigated. Then we considered the wall vortex whose flux goes to infinity. At last, the relationship between the bag model and wall vortices is considered.
2010, 27(4): 436-439.
doi: 10.11804/NuclPhysRev.27.04.436
Abstract:
Superconducting(SC) cavities currently used for acceleration of ions in the velocity range from 0.01 c to 0.3 c are based frequently on quarterwave resonators(QWR). Various types of QWR cavities across a frequency extent from 50 to 240 MHz have been constructed or are proposed for numerous applications. A drawback of this kind of cavities is the beam steering caused by transverse magnetic and electric field components, which can creat emittance growth. In this paper, the analytical studies on beam steering in quarter wave resonator of frequency=80.5 and 161 MHz of the SC linac has been done in Institute of Modern Physics, Chinese Academy of Sciences, the calculated results have told us that the correction for beam deflection should be a consideration during the design of the QWR cavity, which generally involves the shaping the inner drift tube.
Superconducting(SC) cavities currently used for acceleration of ions in the velocity range from 0.01 c to 0.3 c are based frequently on quarterwave resonators(QWR). Various types of QWR cavities across a frequency extent from 50 to 240 MHz have been constructed or are proposed for numerous applications. A drawback of this kind of cavities is the beam steering caused by transverse magnetic and electric field components, which can creat emittance growth. In this paper, the analytical studies on beam steering in quarter wave resonator of frequency=80.5 and 161 MHz of the SC linac has been done in Institute of Modern Physics, Chinese Academy of Sciences, the calculated results have told us that the correction for beam deflection should be a consideration during the design of the QWR cavity, which generally involves the shaping the inner drift tube.
2010, 27(4): 440-444.
doi: 10.11804/NuclPhysRev.27.04.440
Abstract:
The end optimization of dipole magnet of SuperFRS for FAIR by OPERA 3D has been introduced in this paper. By using a complicated chamfer，the integral field homogeneity which is better than 2×10-4 can be obtained. In addition， the paper also introduced the comparison between the magnetic field measurement result and calculation one，which confirms the method of the removable pole end chamfer very well.
The end optimization of dipole magnet of SuperFRS for FAIR by OPERA 3D has been introduced in this paper. By using a complicated chamfer，the integral field homogeneity which is better than 2×10-4 can be obtained. In addition， the paper also introduced the comparison between the magnetic field measurement result and calculation one，which confirms the method of the removable pole end chamfer very well.
2010, 27(4): 445-449.
doi: 10.11804/NuclPhysRev.27.04.445
Abstract:
With the modeling of the light transportation in crystal and electron multiplication in the PMT， a Monte Carlo simulation of CsI(Tl) scintillator detector has been implemented with Geant4 toolkit. The energy spectra simulated with different crystal shape， size and wrappings are obtained. And the reliability of the simulation parameters is confirmed by comparing with the measurements. The simulation code can be used as an reliable tool for the design of scintillator detectors.
With the modeling of the light transportation in crystal and electron multiplication in the PMT， a Monte Carlo simulation of CsI(Tl) scintillator detector has been implemented with Geant4 toolkit. The energy spectra simulated with different crystal shape， size and wrappings are obtained. And the reliability of the simulation parameters is confirmed by comparing with the measurements. The simulation code can be used as an reliable tool for the design of scintillator detectors.
2010, 27(4): 450-454.
doi: 10.11804/NuclPhysRev.27.04.450
Abstract:
The gas detectors have the characteristics of low cost, easy preparation, reliable capability and convenient for use etc. A delay line parallelplate avalanche counter(PPAC) with five plates has been developed for the experiments at Radioactive Ion Beam Line in Lanzhou(RIBLL). The applicability of counter for high energy light ion has been tested with 57.6 MeV/u 6He beam. A position resolution of ~1.8 mm(FWHM) and a timing resolution of ~2.6 ns are achieved. The detection efficiency is reasonable.
The gas detectors have the characteristics of low cost, easy preparation, reliable capability and convenient for use etc. A delay line parallelplate avalanche counter(PPAC) with five plates has been developed for the experiments at Radioactive Ion Beam Line in Lanzhou(RIBLL). The applicability of counter for high energy light ion has been tested with 57.6 MeV/u 6He beam. A position resolution of ~1.8 mm(FWHM) and a timing resolution of ~2.6 ns are achieved. The detection efficiency is reasonable.
2010, 27(4): 455-458.
doi: 10.11804/NuclPhysRev.27.04.455
Abstract:
Design of a novel spectrometer for measurements of neutrons in the energy range 9—17 MeV has been proposed. Based on proton recoil method and magnetic analyzing technigue， the spectrometer can be used to determine DT fuel areal density(<ρR) and ion temperature under steady state and pulsed radiation field. The detection efficiency is about 10-8 for measuring 14 MeV neutrons with an energy resolution of about 4%. A neodymiumironboron permanent dipole was used for the magnetic analyzing system and CR-39 track detectors were used in the focal plane. The system has been tested with 239Pu α suorce and a corresponding particle transport simulation program has been worked out. Performance of the spectrometer was investigated with Monte Carlo simulation，experiment data and the transport simulation. Due to its good performance，compact structure，and availability for both steady state and pulsed radiation field，the spectrometer can be effectively used for fusion research in the future.
Design of a novel spectrometer for measurements of neutrons in the energy range 9—17 MeV has been proposed. Based on proton recoil method and magnetic analyzing technigue， the spectrometer can be used to determine DT fuel areal density(<ρR) and ion temperature under steady state and pulsed radiation field. The detection efficiency is about 10-8 for measuring 14 MeV neutrons with an energy resolution of about 4%. A neodymiumironboron permanent dipole was used for the magnetic analyzing system and CR-39 track detectors were used in the focal plane. The system has been tested with 239Pu α suorce and a corresponding particle transport simulation program has been worked out. Performance of the spectrometer was investigated with Monte Carlo simulation，experiment data and the transport simulation. Due to its good performance，compact structure，and availability for both steady state and pulsed radiation field，the spectrometer can be effectively used for fusion research in the future.
2010, 27(4): 459-463.
doi: 10.11804/NuclPhysRev.27.04.459
Abstract:
In this paper, the objective is to realize a Track/Hold Circuit for silicon strip, Si(Li), CdZnTe and CsI detectors etc. By using CMOS transistor to implement various components in electronic circuit, the Track and Hold circuit only made with CMOS FET is succeeded to be designed and simulated. Performance was characterized using PSPICE simulator with BSIMV3.3 parameters of the Proteus. Several measurements of acquisition time can be made from 60 ns to 4.44us related to the output resistance, and the integral nonlinearity is good.
In this paper, the objective is to realize a Track/Hold Circuit for silicon strip, Si(Li), CdZnTe and CsI detectors etc. By using CMOS transistor to implement various components in electronic circuit, the Track and Hold circuit only made with CMOS FET is succeeded to be designed and simulated. Performance was characterized using PSPICE simulator with BSIMV3.3 parameters of the Proteus. Several measurements of acquisition time can be made from 60 ns to 4.44us related to the output resistance, and the integral nonlinearity is good.
2010, 27(4): 464-468.
doi: 10.11804/NuclPhysRev.27.04.464
Abstract:
It is described in this paper the design of the control system for HIRFLCSRe internal target facility， in which there are many different kinds of units need to be monitored and controlled. The control system is composed of several subsystems which are designed to control the gasjet temperature， chamber vacuum， valves and molecular pumps. A humancomputer interaction interface is also realized to do the data acquisition， data processing and display. The whole system has been working stably and safely， it fully meets the requirements of physical experiments in the internal target facility. In January of 2010， the first physics experiment of the radioactive electron capture was finished successfully with the aids of this control system.
It is described in this paper the design of the control system for HIRFLCSRe internal target facility， in which there are many different kinds of units need to be monitored and controlled. The control system is composed of several subsystems which are designed to control the gasjet temperature， chamber vacuum， valves and molecular pumps. A humancomputer interaction interface is also realized to do the data acquisition， data processing and display. The whole system has been working stably and safely， it fully meets the requirements of physical experiments in the internal target facility. In January of 2010， the first physics experiment of the radioactive electron capture was finished successfully with the aids of this control system.
2010, 27(4): 469-473.
doi: 10.11804/NuclPhysRev.27.04.469
Abstract:
Based on the molecular model of conformation changes of plasmid DNA， the DNA damages induced by γ rays， proton and 7Li ion were studied and compared. In order to detect the clustered DNA damage， the irradiated plasmid DNA was digested with E Coli formamidopyrimidine DNA glycosylase (Fpg) and AP endonuclease III (Endo III) which convert the damaged bases and AP sites into singlestrand breaks (SSB)， and then subjected to agarose gel electrophoresis. The results indicated that SSB， a certain level of clustered bases lesions and a tiny of doublestrand breaks (DSB)were induced by the observed 50—200 Gy of γ rays. The DNA breakage and clustered bases lesions induced by high LET proton and 7Li ion were much higher as compared with that induced by γ rays. Our data also showed that an obvious clustered DNA damage was induced by proton even at 10 Gy dose， and the effectiveness of DNA damage induction by proton was higher than that of 7Li ion.
Based on the molecular model of conformation changes of plasmid DNA， the DNA damages induced by γ rays， proton and 7Li ion were studied and compared. In order to detect the clustered DNA damage， the irradiated plasmid DNA was digested with E Coli formamidopyrimidine DNA glycosylase (Fpg) and AP endonuclease III (Endo III) which convert the damaged bases and AP sites into singlestrand breaks (SSB)， and then subjected to agarose gel electrophoresis. The results indicated that SSB， a certain level of clustered bases lesions and a tiny of doublestrand breaks (DSB)were induced by the observed 50—200 Gy of γ rays. The DNA breakage and clustered bases lesions induced by high LET proton and 7Li ion were much higher as compared with that induced by γ rays. Our data also showed that an obvious clustered DNA damage was induced by proton even at 10 Gy dose， and the effectiveness of DNA damage induction by proton was higher than that of 7Li ion.
2010, 27(4): 474-479.
doi: 10.11804/NuclPhysRev.27.04.474
Abstract:
The influence of cell cluster dimension on EUD and TCP for targeted radionuclide therapy was studied using the radiobiological method. The radiobiological features of tumor with activity lack in core were evaluated and analyzed by associating EUD，TCP and SF. The results show that EUD will increase with the increase of tumor dimension under the activity homogeneous distribution. If the extracellular activity was taken into consideration， the EUD will increase 47%. Under the activity lack in tumor center and the requirement of TCP=0.90， the α crossfire influence of 211At could make up the maximum(48 μm)3 activitylack for Nucleus source， but (72 μm)3 for Cytoplasm， Cell Surface， Cell and Voxel sources. In clinic， the physician could prefer the suggested dose of Cell Surface source in case of the future of local tumor control for underdose. Generally TCP could well exhibit the effect difference between underdose and duedose， but not between duedose and over dose，which makes TCP more suitable for the therapy plan choice. EUD could well exhibit the difference between different models and activity distributions，which makes it more suitable for the research work. When the user uses EUD to study the influence of activity inhomogeneous distribution， he should keep the consistency of the configuration and volume of the former and the latter models.
The influence of cell cluster dimension on EUD and TCP for targeted radionuclide therapy was studied using the radiobiological method. The radiobiological features of tumor with activity lack in core were evaluated and analyzed by associating EUD，TCP and SF. The results show that EUD will increase with the increase of tumor dimension under the activity homogeneous distribution. If the extracellular activity was taken into consideration， the EUD will increase 47%. Under the activity lack in tumor center and the requirement of TCP=0.90， the α crossfire influence of 211At could make up the maximum(48 μm)3 activitylack for Nucleus source， but (72 μm)3 for Cytoplasm， Cell Surface， Cell and Voxel sources. In clinic， the physician could prefer the suggested dose of Cell Surface source in case of the future of local tumor control for underdose. Generally TCP could well exhibit the effect difference between underdose and duedose， but not between duedose and over dose，which makes TCP more suitable for the therapy plan choice. EUD could well exhibit the difference between different models and activity distributions，which makes it more suitable for the research work. When the user uses EUD to study the influence of activity inhomogeneous distribution， he should keep the consistency of the configuration and volume of the former and the latter models.
2010, 27(4): 480-487.
doi: 10.11804/NuclPhysRev.27.04.480
Abstract:
Based on the Heavy Ion Research Facility in Lanzhou(HIRFL/HIRFLCSR)， clinical trials of heavy ion radiotherapy are being conducted at the〖HJ*4/9〗 Institute of Modern Physics(IMP)， Chinese Academy of Sciences， where twodimensional(2D) layerstacking conformal irradiation method in a passive beam delivery system was applied. To make better use of the biophysical advantages of heavy ion beams and ensure success of the clinical trials， a preliminary version of heavy ion treatment planning system(TPS) has been developed at IMP. The TPS was designed in a manner to adapt to the 2D layerstacking conformal irradiation method. The architecture and function of the TPS software and the implementation 〖HJ〗of dose calculation algorithm in the TPS were introduced in this paper. The deviation between the doses planned by the TPS and measured through an anthropomorphous phantom was verified to be less than 5%. Finally， the pending issues for developing a sophisticated treatment planning system at IMP were discussed.
Based on the Heavy Ion Research Facility in Lanzhou(HIRFL/HIRFLCSR)， clinical trials of heavy ion radiotherapy are being conducted at the〖HJ*4/9〗 Institute of Modern Physics(IMP)， Chinese Academy of Sciences， where twodimensional(2D) layerstacking conformal irradiation method in a passive beam delivery system was applied. To make better use of the biophysical advantages of heavy ion beams and ensure success of the clinical trials， a preliminary version of heavy ion treatment planning system(TPS) has been developed at IMP. The TPS was designed in a manner to adapt to the 2D layerstacking conformal irradiation method. The architecture and function of the TPS software and the implementation 〖HJ〗of dose calculation algorithm in the TPS were introduced in this paper. The deviation between the doses planned by the TPS and measured through an anthropomorphous phantom was verified to be less than 5%. Finally， the pending issues for developing a sophisticated treatment planning system at IMP were discussed.
2010, 27(4): 488-492.
doi: 10.11804/NuclPhysRev.27.04.488
Abstract:
Increasing data have been accumulated for the existence and manifestation of radiationinduced bystander effects (RIBE) in the whole organism context. However， the early signaling in RIBE in vivo has been unclear due to the lack of relevant methodology. In the present study，a novel plant experimental system for studying the early signaling in RIBE in vivo was established，in which the expression level of HR related AtRAD54 gene was measured as a biological endpoint， and the root cutting and grafting were used to stop and restore the signaling communication from irradiated roots to bystander aerial plants.
Increasing data have been accumulated for the existence and manifestation of radiationinduced bystander effects (RIBE) in the whole organism context. However， the early signaling in RIBE in vivo has been unclear due to the lack of relevant methodology. In the present study，a novel plant experimental system for studying the early signaling in RIBE in vivo was established，in which the expression level of HR related AtRAD54 gene was measured as a biological endpoint， and the root cutting and grafting were used to stop and restore the signaling communication from irradiated roots to bystander aerial plants.
2010, 27(4): 493-499.
doi: 10.11804/NuclPhysRev.27.04.493
Abstract:
Jinsha Ruins Site, Chengdu, China, spanned the age from late Shang Dynasty to Western Zhou Dynasty (B.C.1200—B.C.650), was generally considered as the inheritance of Sanxingdui Culture. This paper focuses on the studies of the pottery unearthed from Jinsha. PIXE and RBS experimental setup was preliminarily established and these techniques were employed to find the elemental composition of those collected shards. From the results of factor analysis, the differences can be seen among pottery shards from different stratums, which may suggest that the clay gathered from different sites was used in different periods. The authors also found that there was no obvious assemblage phenomenon in the factor analysis among the pottery shards from different pits, this may be the evidence for “no special clay for special use”.
Jinsha Ruins Site, Chengdu, China, spanned the age from late Shang Dynasty to Western Zhou Dynasty (B.C.1200—B.C.650), was generally considered as the inheritance of Sanxingdui Culture. This paper focuses on the studies of the pottery unearthed from Jinsha. PIXE and RBS experimental setup was preliminarily established and these techniques were employed to find the elemental composition of those collected shards. From the results of factor analysis, the differences can be seen among pottery shards from different stratums, which may suggest that the clay gathered from different sites was used in different periods. The authors also found that there was no obvious assemblage phenomenon in the factor analysis among the pottery shards from different pits, this may be the evidence for “no special clay for special use”.
2010, 27(4): 500-504.
doi: 10.11804/NuclPhysRev.27.04.500
Abstract:
The energy spectra of emitted electrons in transfer ionization process of 70 and 100 keV He2+ colliding on He haev been measured by using Reaction Microscope . The energy spectra of the ejected electrons have been obtained in the angular range from 0° to 45° and energies from 0 to 45 eV. The characteristics of the energy spectra were analyzed. There is a maximum in each energy spectrum related to different emission angles; The position of the maximum decreases with increasing the emission angle; The velocity of emitted electrons is between 0 and vp， where vp is the projectile velocity; Most electrons are around 0 eV when electron emission angle is 45°. These characteristic could be qualitatively explained in a “quasimolecule” model. The ECC electrons were observed in the transfer ionization process of 100 keV He2+ colliding on He collision， It could be explained as dynamical twostep process.
The energy spectra of emitted electrons in transfer ionization process of 70 and 100 keV He2+ colliding on He haev been measured by using Reaction Microscope . The energy spectra of the ejected electrons have been obtained in the angular range from 0° to 45° and energies from 0 to 45 eV. The characteristics of the energy spectra were analyzed. There is a maximum in each energy spectrum related to different emission angles; The position of the maximum decreases with increasing the emission angle; The velocity of emitted electrons is between 0 and vp， where vp is the projectile velocity; Most electrons are around 0 eV when electron emission angle is 45°. These characteristic could be qualitatively explained in a “quasimolecule” model. The ECC electrons were observed in the transfer ionization process of 100 keV He2+ colliding on He collision， It could be explained as dynamical twostep process.
2010, 27(4): 505-509.
doi: 10.11804/NuclPhysRev.27.04.505
Abstract:
Using cold target recoilion momentum spectroscopy(COLTRIMS) we have measured the momenta of recoil target ions in the single ionization(e， 2e) reactions of Ne at the energies between 70 and 3300 eV. A simple collision mechanism was introduced to analyze the distributions of the momenta of recoil ions. This mechanism can qualitatively well explain the distributions for the intermediate and high impact energy. Finally，the energy range of the ionized electron according to the momenta of the ion was estimated，which lays the foundation for the next coincidence measurement of electrons and ions.
Using cold target recoilion momentum spectroscopy(COLTRIMS) we have measured the momenta of recoil target ions in the single ionization(e， 2e) reactions of Ne at the energies between 70 and 3300 eV. A simple collision mechanism was introduced to analyze the distributions of the momenta of recoil ions. This mechanism can qualitatively well explain the distributions for the intermediate and high impact energy. Finally，the energy range of the ionized electron according to the momenta of the ion was estimated，which lays the foundation for the next coincidence measurement of electrons and ions.
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