2010 Vol. 27, No. 1
Display Method:
2010, 27(1): 1-15.
doi: 10.11804/NuclPhysRev.27.01.001
Abstract:
Some topics on nucleonnucleon(NN) collisions in medium and high energy nuclear physics are reviewed with emphasis on those which are expected to be relevant at the HIRFLCSR Facility. It is mainly concerned with the description of shortrange NN nuclear force， the recent results from STAR and PHENIX experiments in relativistic collisions of nuclei from each other，addressing questions about the role of NN collisions at highenergy，especially for strangeness production and heavy flavor production. Recent progress and some unresolved issues are also concerned. We expect that the results of the present work will lead to a better understanding on the importance of NN collisions at medium and highenergy.
Some topics on nucleonnucleon(NN) collisions in medium and high energy nuclear physics are reviewed with emphasis on those which are expected to be relevant at the HIRFLCSR Facility. It is mainly concerned with the description of shortrange NN nuclear force， the recent results from STAR and PHENIX experiments in relativistic collisions of nuclei from each other，addressing questions about the role of NN collisions at highenergy，especially for strangeness production and heavy flavor production. Recent progress and some unresolved issues are also concerned. We expect that the results of the present work will lead to a better understanding on the importance of NN collisions at medium and highenergy.
2010, 27(1): 16-22.
doi: 10.11804/NuclPhysRev.27.01.016
Abstract:
We develop a jetphoton conversion mechanism in the expanding quark gluon plasma. The jetphoton conversion in hot quarkgluon medium is a vital source of the thermal photon production. The jet converts into photons via the secondary Compton and annihilation processes in the quarkgluon plasma. The gluonphotons are also considered in the calculation of prompt photons which includes the effect of the shadowing and isospin of nucleus. We find that the prompt gluonphotons are also an important modification to prompt photons.
We develop a jetphoton conversion mechanism in the expanding quark gluon plasma. The jetphoton conversion in hot quarkgluon medium is a vital source of the thermal photon production. The jet converts into photons via the secondary Compton and annihilation processes in the quarkgluon plasma. The gluonphotons are also considered in the calculation of prompt photons which includes the effect of the shadowing and isospin of nucleus. We find that the prompt gluonphotons are also an important modification to prompt photons.
2010, 27(1): 23-28.
doi: 10.11804/NuclPhysRev.27.01.023
Abstract:
Nucleus-nucleus collisions are simply regarded as sum of nucleon-nucleon collisions. Particle sources produced by nucleon\|nucleon collisions are treated as classical current. For the classical current formalism ensemble of space-time function there are two terms in two identical particle Bose-Einstein correlation function when sources are partially coherent and one is called coherent term, the other is chaotic one. According to Monte Carlo simulating theory, the algorithm for calculating correlation function of partially coherent sources is derived by generalizing chaotic one. The correlation function of partially coherent sources is simulated by this method at out and side direction of relative momentum, and the out radius of sources from the fitted result is approximately equal to the side one within the error range
Nucleus-nucleus collisions are simply regarded as sum of nucleon-nucleon collisions. Particle sources produced by nucleon\|nucleon collisions are treated as classical current. For the classical current formalism ensemble of space-time function there are two terms in two identical particle Bose-Einstein correlation function when sources are partially coherent and one is called coherent term, the other is chaotic one. According to Monte Carlo simulating theory, the algorithm for calculating correlation function of partially coherent sources is derived by generalizing chaotic one. The correlation function of partially coherent sources is simulated by this method at out and side direction of relative momentum, and the out radius of sources from the fitted result is approximately equal to the side one within the error range
2010, 27(1): 29-31.
doi: 10.11804/NuclPhysRev.27.01.029
Abstract:
In the study of hadronic interaction in the forward region by the simulation of cosmic ray, it is necessary to simulate large numbers of cosmic ray events with low first interaction height. We confirmed that by reducing the FIXCHI the efficiency of cosmic ray simulation can be improved. But the calibration for energy slope is needed. We got the energy slope based on the probability of direct arrived events with energy of 1 TeV, and fitted the intensity of spectrum with energy to make certain the energy slope of high energy cosmic ray. By this way, the efficiency and precision of cosmic ray simulation is greatly improved.
In the study of hadronic interaction in the forward region by the simulation of cosmic ray, it is necessary to simulate large numbers of cosmic ray events with low first interaction height. We confirmed that by reducing the FIXCHI the efficiency of cosmic ray simulation can be improved. But the calibration for energy slope is needed. We got the energy slope based on the probability of direct arrived events with energy of 1 TeV, and fitted the intensity of spectrum with energy to make certain the energy slope of high energy cosmic ray. By this way, the efficiency and precision of cosmic ray simulation is greatly improved.
2010, 27(1): 32-37.
doi: 10.11804/NuclPhysRev.27.01.032
Abstract:
We have reanalyzed the experimental data of inbeam γ spectroscopy for 172Re via the 149Sm(27Al, 4n)172Re reaction. Three rotational bands have been newly found and assigned to 172Re. A new level scheme of 172Re, consisting of 6 bands, is thus presented. Based on the existing knowlegde from the neighboring nuclei and the cranked shell model, the quasiparticle configurtions have been assigned to the 3 newly observed bands and their structure properties have been dicussed.
We have reanalyzed the experimental data of inbeam γ spectroscopy for 172Re via the 149Sm(27Al, 4n)172Re reaction. Three rotational bands have been newly found and assigned to 172Re. A new level scheme of 172Re, consisting of 6 bands, is thus presented. Based on the existing knowlegde from the neighboring nuclei and the cranked shell model, the quasiparticle configurtions have been assigned to the 3 newly observed bands and their structure properties have been dicussed.
2010, 27(1): 38-42.
doi: 10.11804/NuclPhysRev.27.01.038
Abstract:
The total binding energy of nuclei for Zr isotopic chain is calculated by the spherical and axial deformed relativistic meanfield(RMF) theory respectively, and the energy contribution due to the deformation(i.e., deformation correction energy) is extracted. It is found that the neutronrich nuclei in the isotopic chain have large prolate deformation, and corresponding deformation correction energy can be up to 10 MeV. The shell correction energy is obtained by the difference between the binding energies calculated by the liquid model and those by the RMF calculations. Detailed analysis indicates that the deformation weakens the shell effect of N=50 remarkably. Especially for the neutronrich nuclei, large deformation leads to disappearance of the N=50 shell structure.
The total binding energy of nuclei for Zr isotopic chain is calculated by the spherical and axial deformed relativistic meanfield(RMF) theory respectively, and the energy contribution due to the deformation(i.e., deformation correction energy) is extracted. It is found that the neutronrich nuclei in the isotopic chain have large prolate deformation, and corresponding deformation correction energy can be up to 10 MeV. The shell correction energy is obtained by the difference between the binding energies calculated by the liquid model and those by the RMF calculations. Detailed analysis indicates that the deformation weakens the shell effect of N=50 remarkably. Especially for the neutronrich nuclei, large deformation leads to disappearance of the N=50 shell structure.
2010, 27(1): 43-47.
doi: 10.11804/NuclPhysRev.27.01.043
Abstract:
The efficient electron cooling requires that the ion beam and electron beam are parallel and overlapped. In order to measure the positions of ion beam and electron beam simultaneously， a beam position monitor system is developed for the HIRFL-CSR electron cooler device， which probe consists of four capacitive cylinder linearcut poles. One can get the both beam positions from the picking up signals of four poles by using Fourier transform(FFT) method. The measurement results show that the beam position monitor system is accurate. This system is suitable for investigating the relation between electron cooling processing and the angle of ion beam and electron beam.
The efficient electron cooling requires that the ion beam and electron beam are parallel and overlapped. In order to measure the positions of ion beam and electron beam simultaneously， a beam position monitor system is developed for the HIRFL-CSR electron cooler device， which probe consists of four capacitive cylinder linearcut poles. One can get the both beam positions from the picking up signals of four poles by using Fourier transform(FFT) method. The measurement results show that the beam position monitor system is accurate. This system is suitable for investigating the relation between electron cooling processing and the angle of ion beam and electron beam.
2010, 27(1): 48-51.
doi: 10.11804/NuclPhysRev.27.01.048
Abstract:
The method which builds a buncher with nonresonant cavity through the direct production of sawtooth wave has already been applied commonly to accelerator technologies all over the world. Recently, with the rapid development of electronic and mechanical manufacture technology during the last few decades, it leads to develop a sawtooth buncher easily, furthermore, it can improve match efficiency and operation stability in HIRFL at IMP. It has been concluded that the design can be applied to more sophisticated specification according to this method and the measurement of building higher voltage buncher is feasible. At last, we complement critical points involved implementation of this project and makes it work efficiently because of the highest demand and more rigorous installation limitation of this new buncher throughout the world.
The method which builds a buncher with nonresonant cavity through the direct production of sawtooth wave has already been applied commonly to accelerator technologies all over the world. Recently, with the rapid development of electronic and mechanical manufacture technology during the last few decades, it leads to develop a sawtooth buncher easily, furthermore, it can improve match efficiency and operation stability in HIRFL at IMP. It has been concluded that the design can be applied to more sophisticated specification according to this method and the measurement of building higher voltage buncher is feasible. At last, we complement critical points involved implementation of this project and makes it work efficiently because of the highest demand and more rigorous installation limitation of this new buncher throughout the world.
2010, 27(1): 52-55.
doi: 10.11804/NuclPhysRev.27.01.052
Abstract:
Dynamic aperture(DA) is playing a more and more important role in circular accelerators, especially in the modern storage rings. In this paper, the DA of CSRe is analyzed by MAD program. Comparing the DA under various assumptions, we find that the multipole errors in dipoles or quadrupoles, and the sextupoles which bring strong nonlinearities, and limit the DA of CSRe. Fortunately, the DA is larger than the physical aperture in all the cases, and that is large enough to satisfy the high precision physical experimental request.
Dynamic aperture(DA) is playing a more and more important role in circular accelerators, especially in the modern storage rings. In this paper, the DA of CSRe is analyzed by MAD program. Comparing the DA under various assumptions, we find that the multipole errors in dipoles or quadrupoles, and the sextupoles which bring strong nonlinearities, and limit the DA of CSRe. Fortunately, the DA is larger than the physical aperture in all the cases, and that is large enough to satisfy the high precision physical experimental request.
2010, 27(1): 56-62.
doi: 10.11804/NuclPhysRev.27.01.056
Abstract:
A new design of lookuptable(LUT) electronics for a small animal positron emission tomography(PET) system is proposed. Position and energy signals for a coincidence event are generated in a coincidence circuit board and sent to the LUT board， in which the centroid of this event is calculated by the LUT approach. The centroid is used as an index of the crystal element. Corresponding coordinates and energy threshold of this crystal are obtained from the other tables， and the scattered events are rejected. Interfaces for receiving respiratory and electrocardiac gate signals are designed for future use. All the lookup tables are stored in NOR flash memory which is controlled by a Complex Programmable Logic Device. The LUT board communicates with PC through Ethernet board. The advantage of this specific hardware design is that the LUT operation can be performed in a more efficient way， with a <100 ns time delay. The paper also describes the operation of the flashmemory with a CPLD， and the data flow between this LUT and other modules in our PET system.
A new design of lookuptable(LUT) electronics for a small animal positron emission tomography(PET) system is proposed. Position and energy signals for a coincidence event are generated in a coincidence circuit board and sent to the LUT board， in which the centroid of this event is calculated by the LUT approach. The centroid is used as an index of the crystal element. Corresponding coordinates and energy threshold of this crystal are obtained from the other tables， and the scattered events are rejected. Interfaces for receiving respiratory and electrocardiac gate signals are designed for future use. All the lookup tables are stored in NOR flash memory which is controlled by a Complex Programmable Logic Device. The LUT board communicates with PC through Ethernet board. The advantage of this specific hardware design is that the LUT operation can be performed in a more efficient way， with a <100 ns time delay. The paper also describes the operation of the flashmemory with a CPLD， and the data flow between this LUT and other modules in our PET system.
2010, 27(1): 63-67.
doi: 10.11804/NuclPhysRev.27.01.063
Abstract:
The multianode position sensitive photomultiplier tube(PSPMT) has been used for the development of highresolution γ camera module. This study is aimed to investigate the simplified readout design for the multianode flat panel PSPMT. Based on the Hamamatsu H8500 PSPMT with 64 multianodes, we designed and developed two simplified readout circuits, discretized positioning circuit(DPC) and symmetric charge division circuit(SCDC). The truncated centerofgravity(TCOG) positioning method was used to optimize the readout signal processing and then further reduce the readout channels by a resistor chain. The preliminary results show that the SCDC readout with the TCOG could significantly reduce the nonlinearity of positioning and improve the effective fieldofview of the detector by about 20% as compared to the DPC readout.
The multianode position sensitive photomultiplier tube(PSPMT) has been used for the development of highresolution γ camera module. This study is aimed to investigate the simplified readout design for the multianode flat panel PSPMT. Based on the Hamamatsu H8500 PSPMT with 64 multianodes, we designed and developed two simplified readout circuits, discretized positioning circuit(DPC) and symmetric charge division circuit(SCDC). The truncated centerofgravity(TCOG) positioning method was used to optimize the readout signal processing and then further reduce the readout channels by a resistor chain. The preliminary results show that the SCDC readout with the TCOG could significantly reduce the nonlinearity of positioning and improve the effective fieldofview of the detector by about 20% as compared to the DPC readout.
2010, 27(1): 68-70.
doi: 10.11804/NuclPhysRev.27.01.068
Abstract:
The light output and energy resolution of PbWO4 crystal are studied with different wrapping materials and methods. The Wrapping condition was optimized by analyzing the experimental data to gain higher light output and better energy resolution. A GEANT4based package has been developed to simulate the corresponding features of PbWO4 crystal, and the simulation results are consistent with the experimental data.
The light output and energy resolution of PbWO4 crystal are studied with different wrapping materials and methods. The Wrapping condition was optimized by analyzing the experimental data to gain higher light output and better energy resolution. A GEANT4based package has been developed to simulate the corresponding features of PbWO4 crystal, and the simulation results are consistent with the experimental data.
2010, 27(1): 71-76.
doi: 10.11804/NuclPhysRev.27.01.071
Abstract:
The distribution of longlived isotope 36Cl (T1/2=3.01×105 a) is widely spread in the world. Accelerator mass spectrometry(AMS) is presently the most sensitive method for the measurement of 36Cl. The sample preparation and AMS measurement procedure are briefly introduced. The detection methods based on the “small” AMS are also introduced, as well as their performance. The research progress on applications of 36Cl in various laboratories around the world is reviewed.
The distribution of longlived isotope 36Cl (T1/2=3.01×105 a) is widely spread in the world. Accelerator mass spectrometry(AMS) is presently the most sensitive method for the measurement of 36Cl. The sample preparation and AMS measurement procedure are briefly introduced. The detection methods based on the “small” AMS are also introduced, as well as their performance. The research progress on applications of 36Cl in various laboratories around the world is reviewed.
2010, 27(1): 77-81.
doi: 10.11804/NuclPhysRev.27.01.077
Abstract:
In accuracy radiotherapy, it is difficult to calculate dose accurately during wedge fields. In this paper, an improved corrected algorithm of wedges based on the lineattenuation was proposed. The lineattenuation coefficient of wedges was calculated firstly, then the actual path of radial beam in the wedge was calculated by the “linear fitting” according to the sizes of wedges section. Finally the wedge factors could be determined accurately， and the dose could be corrected. The data of the 45 degree wedge in the report of AAPM 55 were used to make the calculation and verificaton. Using this algorithm,amount of measured data were decreased, the accuracy of calculation could be assured， and the job of physician could be reduced,so this algorithm could be applied in the treatment planning system as an effective calculation method of wedges field.
In accuracy radiotherapy, it is difficult to calculate dose accurately during wedge fields. In this paper, an improved corrected algorithm of wedges based on the lineattenuation was proposed. The lineattenuation coefficient of wedges was calculated firstly, then the actual path of radial beam in the wedge was calculated by the “linear fitting” according to the sizes of wedges section. Finally the wedge factors could be determined accurately， and the dose could be corrected. The data of the 45 degree wedge in the report of AAPM 55 were used to make the calculation and verificaton. Using this algorithm,amount of measured data were decreased, the accuracy of calculation could be assured， and the job of physician could be reduced,so this algorithm could be applied in the treatment planning system as an effective calculation method of wedges field.
2010, 27(1): 82-86.
doi: 10.11804/NuclPhysRev.27.01.082
Abstract:
Mutagenic effect on avermectin B1a producing strains of ZJAV-A1 by ion beam of 12C6+ has been investigated.The experimental results indicated that the lethality was 97% and the highest rate of orthomutation was 34.2%， when ZJAVA1 was irradiated by ion beam of 50 Gy 12C6+. After the mutagenesis processing by ion beam of 12C6+ and the screening of orthomutation strains by using plating mediums and slant cultures，the mutant ZJAV-Y1203 was obtained with theavermectin B1a yield of 4588—4460 μg/ml. Compared with the original strain， the titer was improved 11.1%—14.7%.
Mutagenic effect on avermectin B1a producing strains of ZJAV-A1 by ion beam of 12C6+ has been investigated.The experimental results indicated that the lethality was 97% and the highest rate of orthomutation was 34.2%， when ZJAVA1 was irradiated by ion beam of 50 Gy 12C6+. After the mutagenesis processing by ion beam of 12C6+ and the screening of orthomutation strains by using plating mediums and slant cultures，the mutant ZJAV-Y1203 was obtained with theavermectin B1a yield of 4588—4460 μg/ml. Compared with the original strain， the titer was improved 11.1%—14.7%.
2010, 27(1): 87-91.
doi: 10.11804/NuclPhysRev.27.01.087
Abstract:
ZnO thin films were implanted at the room temperature by 80 keV N-ions to 5.0×1014, 5.0×1015 or 5.0×1016 ions/cm2, the structural characteristics of the samples were investigated using X-ray diffraction(XRD) spectrometer and transmission electron microscopy(TEM). It was found that the un-implanted ZnO films are constituted of columnar crystals which are very compact and of preferred c-axis orientation. After N-ion implantation, the crystal lattice constant and the biaxial compressive stress increased with the increasing of the N-implantation dose. In the 5.0×1016 N-ions/cm2 implanted ZnO sample, a new XRD peak due to defects or N-dopants appeared. Moreover, defects and localized disordering in the 5.0×1015 N-ions/cm2 implanted ZnO films have been observed under high resolution TEM measurement. However, N-ion implantation could not change significantly the crystal structure of the ZnO films. Possible mechanism of the structural modification of ZnO films by N-ion implantation was briefly discussed.
ZnO thin films were implanted at the room temperature by 80 keV N-ions to 5.0×1014, 5.0×1015 or 5.0×1016 ions/cm2, the structural characteristics of the samples were investigated using X-ray diffraction(XRD) spectrometer and transmission electron microscopy(TEM). It was found that the un-implanted ZnO films are constituted of columnar crystals which are very compact and of preferred c-axis orientation. After N-ion implantation, the crystal lattice constant and the biaxial compressive stress increased with the increasing of the N-implantation dose. In the 5.0×1016 N-ions/cm2 implanted ZnO sample, a new XRD peak due to defects or N-dopants appeared. Moreover, defects and localized disordering in the 5.0×1015 N-ions/cm2 implanted ZnO films have been observed under high resolution TEM measurement. However, N-ion implantation could not change significantly the crystal structure of the ZnO films. Possible mechanism of the structural modification of ZnO films by N-ion implantation was briefly discussed.
2010, 27(1): 92-96.
doi: 10.11804/NuclPhysRev.27.01.092
Abstract:
Monocrystalline silicon(cSi), thin films of amorphous silicon(aSi) and nanocrystalline silicon(ncSi) were irradiated at room temperature(RT) by using 94 MeV Xeions at 1.0×1011, 1.0×1012 or 1.0×1013 Xeions/cm2, respectively. All samples were analyzed at RT by an UV/VIS/NIR spectrometer (Lambda 900, PE, Germany), and then the uariation of the optical bandgap with the irradiation fluence was investigated systematically. The results show that the optical bandgap of the silicon samples irradiates by Xeion changed dramatically with different crystalline structures. For the aSi thin films, the optical bandgap values decreased gradually from ~1.78 to ~1.54 eV with increasing Xeion irradiation fluence. For the ncSi thin films, the optical bandgap values increased sharply from ~1.50 (origin) to ~1.81 eV(Φ=1.0×1012ions/cm2), and then decreased to ~1.67 eV(Φ=1.0×1013 ions/cm2). However, there is no observable change of the optical bandgap of the cSi after Xeion irradiations. Possible mechanism on the modification of the silicon thin films was briefly discussed.
Monocrystalline silicon(cSi), thin films of amorphous silicon(aSi) and nanocrystalline silicon(ncSi) were irradiated at room temperature(RT) by using 94 MeV Xeions at 1.0×1011, 1.0×1012 or 1.0×1013 Xeions/cm2, respectively. All samples were analyzed at RT by an UV/VIS/NIR spectrometer (Lambda 900, PE, Germany), and then the uariation of the optical bandgap with the irradiation fluence was investigated systematically. The results show that the optical bandgap of the silicon samples irradiates by Xeion changed dramatically with different crystalline structures. For the aSi thin films, the optical bandgap values decreased gradually from ~1.78 to ~1.54 eV with increasing Xeion irradiation fluence. For the ncSi thin films, the optical bandgap values increased sharply from ~1.50 (origin) to ~1.81 eV(Φ=1.0×1012ions/cm2), and then decreased to ~1.67 eV(Φ=1.0×1013 ions/cm2). However, there is no observable change of the optical bandgap of the cSi after Xeion irradiations. Possible mechanism on the modification of the silicon thin films was briefly discussed.
2010, 27(1): 97-101.
doi: 10.11804/NuclPhysRev.27.01.097
Abstract:
At room temperature， polyethylene terephthalate(PET) foil stacks were irradiated by 25 MeV/u Kr ions in the electronic stopping power range(3.3--7.66 keV/nm) and the fluence range from 5×1011 to 3×1012 ions/cm2. The behaviour of the main function groups with fluence and electronic stopping power were studied by using Fouriertransforminfrared(FTIR) spectroscopy， the degradation of the function group was investigated with the Lorentz fitting subtracted baseline. The amorphous processes in the latent tracks of PET were studied by Xray diffraction(XRD) measurements. The Kr ion induced degradation crosssection and amorphisation crosssections(radii) for different electronic energy loss were acquired from the experimental data(FTIR and XRD) by exponential decay function respectively.
At room temperature， polyethylene terephthalate(PET) foil stacks were irradiated by 25 MeV/u Kr ions in the electronic stopping power range(3.3--7.66 keV/nm) and the fluence range from 5×1011 to 3×1012 ions/cm2. The behaviour of the main function groups with fluence and electronic stopping power were studied by using Fouriertransforminfrared(FTIR) spectroscopy， the degradation of the function group was investigated with the Lorentz fitting subtracted baseline. The amorphous processes in the latent tracks of PET were studied by Xray diffraction(XRD) measurements. The Kr ion induced degradation crosssection and amorphisation crosssections(radii) for different electronic energy loss were acquired from the experimental data(FTIR and XRD) by exponential decay function respectively.
2010, 27(1): 102-106.
doi: 10.11804/NuclPhysRev.27.01.102
Abstract:
The polypropylene membranes were irradiated by 197Au ions of energy 11.4 MeV/u and fluences 1×108 ions/cm2 at a normal incidence. Sulfuric acid and potassium dichromate solution were employed as the etchant to etch the ion tracks. The influences of the temperature and the concentration of each ingredient were systematically investigated by recording the electrical current during etching process. The nanoporous with different shapes were successfully prepared with homogenous porous of diameters from 600 nm to 1 μm. The morphology of the porous was analyzed by scanning electron microscopy(SEM). The experiment has provided a method for production of the lithiumion battery separator.
The polypropylene membranes were irradiated by 197Au ions of energy 11.4 MeV/u and fluences 1×108 ions/cm2 at a normal incidence. Sulfuric acid and potassium dichromate solution were employed as the etchant to etch the ion tracks. The influences of the temperature and the concentration of each ingredient were systematically investigated by recording the electrical current during etching process. The nanoporous with different shapes were successfully prepared with homogenous porous of diameters from 600 nm to 1 μm. The morphology of the porous was analyzed by scanning electron microscopy(SEM). The experiment has provided a method for production of the lithiumion battery separator.
2010, 27(1): 107-112.
doi: 10.11804/NuclPhysRev.27.01.107
Abstract:
In the frame of classical physics and the dipole approximation the radiation frequency and the spectral distribution are derived for the channeling radiation of a charged particle in a superlattice quantum well. It indicated that there is a linetype factor f(ξ) suited to various cases in the spontaneous radiations spectrum. Results also show that the maximum radiation energy is proportional to γ3/2 , but the relativistic effects have double effects in the spontaneous radiation of a charged particle. The case for the sinesquared potential is discussed specifically. The harmonic number can be defined as a few variable values by the effects of the potential well depth and noise. In general there is a few spectral lines in the channeling radiation spectrum for the superlattice quantum well, and possibilities are provided for further application. Finally, a possible experimental scheme is proposed, and it is discussed that how to transform the channeling radiation in the quantum well into the cohenent radiation by the bent crystal.
In the frame of classical physics and the dipole approximation the radiation frequency and the spectral distribution are derived for the channeling radiation of a charged particle in a superlattice quantum well. It indicated that there is a linetype factor f(ξ) suited to various cases in the spontaneous radiations spectrum. Results also show that the maximum radiation energy is proportional to γ3/2 , but the relativistic effects have double effects in the spontaneous radiation of a charged particle. The case for the sinesquared potential is discussed specifically. The harmonic number can be defined as a few variable values by the effects of the potential well depth and noise. In general there is a few spectral lines in the channeling radiation spectrum for the superlattice quantum well, and possibilities are provided for further application. Finally, a possible experimental scheme is proposed, and it is discussed that how to transform the channeling radiation in the quantum well into the cohenent radiation by the bent crystal.
2010, 27(1): 113-119.
doi: 10.11804/NuclPhysRev.27.01.113
Abstract:
Collective state and transfer reaction are considered in this paper. The energy spectra and double differential cross sections of neutron, proton, alpha, deuteron, triton and helium\|3 emissions are calculated for p+58Ni reaction below 200 MeV with the theoretical model code MEND. The theoretical results agree with the corresponding experimental data. This work accounts for the peaks of the energy spectra and the double differential cross sections, and reduced the values of the single particle state density parameter ccg1(v).
Collective state and transfer reaction are considered in this paper. The energy spectra and double differential cross sections of neutron, proton, alpha, deuteron, triton and helium\|3 emissions are calculated for p+58Ni reaction below 200 MeV with the theoretical model code MEND. The theoretical results agree with the corresponding experimental data. This work accounts for the peaks of the energy spectra and the double differential cross sections, and reduced the values of the single particle state density parameter ccg1(v).
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