Articles in press have been peer-reviewed and accepted, which are not yet assigned to volumes /issues, but are citable by Digital Object Identifier (DOI).
Display Method:
Abstract(0) HTML(0) PDF (1129KB)(0)
Abstract:
Methods and criteria for the identification of male individual radiosensitivity are investigated. The peripheral blood of 50 male volunteers was irradiated with different doses of X-ray, the micronucleus frequency rate (MNF) was measured by cytokinesis-block micronucleus assay, and the central standard curve of micronucleus dose effect was drawn by second-order multinomial fitting method so that the individual dose-response curve of micronucleus was compared with the standard curve to judge individual radiosensitivity. In the dose range of 0.0~2.5 Gy, the central equation of second-order polynomial fit for dose effect is (MNF=0.014 7+0.036 2D+0.023 1D2, R=0.726). Among the 50 male volunteers, 13 were sensitive to radiation (26.0%) and 14 were resistant (28.0%), which basically fits the normal distribution. Spearman rank correlation analysis showed that the MNF increased with the dose and there was a positive correlation between the background MNF and the radiosensitivity of each dose, but negative correlation with the radioresistance. In conclusion, a "curve-instead-of-dose" male individual radiosensitivity identification method was established. Moreover, it was found that the background of micronuclei in peripheral blood lymphocytes was positively correlated with individual radiosensitivity.
Abstract(0) HTML(0) PDF (1024KB)(0)
Abstract:
Most of the existing methods for beam control using magnet field use the open-loop mode, which is to directly set the value of current and voltage of the magnet power supply output based on the demand of magnetic field intensity. However, magnetic fields in the open-loop state are easy to be deflected due to the field noise and the eddy current effect of the magnet. To solve this problem, the closed-loop control system of the magnetic field based on the PID algorithm is developed in this article. This system takes the deflection magnet as the control object, uses the Hall sensor to obtain the magnetic field intensity as the feedback, and utilizes the output of the excitation current of the magnet power supply as the input of the control system. The controller uses the PID algorithm to automatically tune the output of the magnet power supply to achieve the closed-loop control of the magnetic field. The result shows that when the PID parameters are properly set, the magnetic field offset can be significantly reduced by the closed-loop control method which takes the online measured value of the magnetic field as the feedback signal to simultaneously tune the excitation current value of the magnet power supply.
Abstract(0) HTML(0) PDF (2087KB)(0)
Abstract:
The CSR External-target Experiment(CEE) system under development may reach an average data rate of 2 GB/s after being triggered. In response to the design requirements of the entire spectrometer, a generic stream processing data acquisition architecture D-Matrix is put forward in the article, and a specific scheme of D-Matrix in the Time-of-Flight detector(TOF) subsystem is proposed. The DAQ of the TOF system uses high-speed serial communication methods such as optical fiber and PCIe bus to complete data transmission from Front-End Electronics(FEE) to the servers, and deploys and cascades stream processing nodes with a unified interface to complete event building, command routing, Real-time status monitoring and displaying and data storage tasks. In addition, the DAQ of the TOF system has strong versatility in hardware and logic design, it also can be compatible with other sub-detector systems, and can be further applied to the global system of CEE experiments.
Abstract(0) HTML(0) PDF (2546KB)(0)
Abstract:
The multinucleon transfer reaction processes of $^{136}{\rm{Xe}}$+$^{198}{\rm{Pt}}$ are investigated by using the ImQMD model. The TKE-Mass distributions of binary fragments at different contact time scales are analysed. It is found that the quasielastic collisions, the deep-inelastic collisions and the quasifission reactions can be roughly distinguished by the contact time. By analysing the double differential cross sections of the TLFs and the isotopic cross sections of Ba nuclei under the different contact time, we find that the neutron-rich nuclei are produced in the deep-inelastic collisions. In addition, the TLFs with emission angle around 0° are produced in central collisions for the reactions of $^{136}{\rm{Xe}}$+$^{198}{\rm{Pt}}$.
Abstract(0) HTML(0) PDF (1532KB)(0)
Abstract:
Direct production of 99Mo and 99mTc with accelerator has a good development prospect in the field of nuclear medicine. Accurate and reliable nuclear reaction data is of great significance for isotope production. In this paper, the cross sections for natMo(p, x)96m+gTc, 100Mo(p, x)99Mo and 100Mo(p, 2n)99mTc reactions being taken from EXFOR database have been analyzed, and the experimental data were fitted by polynomial fit method. The excitation functions of natMo(p, x)96m+gTc、100Mo(p, x)99Mo and 100Mo(p, 2n)99mTc reactions were calculated up to 40 MeV by using TALYS-1.95 and EMPIRE-3.2.3 code with different energy level density and pre-equilibrium emission models. For the natMo(p, x)96m+gTc reaction, the calculation results predicted by preeqmode 1, 2 models are in good agreement with the experimental data when the input parameter ldmodel 6 of level density is used in TALYS-1.95 code. For the 100Mo(p, x)99Mo reaction, the calculation results predicted by preeqmode 4 models are in good agreement with the experimental data when the input parameter ldmodel 6 of level density is used in TALYS-1.95 code. For the 100Mo(p, 2n)99mTc reaction, the calculated results predicted by LEVDEN 2 in EMPIRE-3.2.3 code are in good agreement with the experimental data.
Abstract(0) HTML(0) PDF (2756KB)(0)
Abstract:
The Heavy Ion Research Facility in Lanzhou(HIRFL) is the largest heavy ion research facility in China, which has the most kinds of accelerated ions and the highest energy. Radiation will be generated in the accelerator tunnel during the operation of HIRFL, so it is necessary to establish a radiation safety interlock system to ensure the radiation safety of the workers. The system folows the design principles of zone partition interlocking, reliable hardware, failure protection, redundancy and independence, self-locking, etc. Redundant PLCs with high reliability are used as the central controller and interlocking components with high safety are selected. The successful establishment of the radiation safety interlock system is of great significance to the radiation safety of the staff at HIRFL, and it can also provide a reference for the design of interlock systems of other accelerators.
Abstract(0) HTML(0) PDF (1359KB)(0)
Abstract:
The atmospheric cosmogenic nuclides of 10Be, 7Be, 22Na are of great significance to research on global climate change and atmospheric environmental governance, as the sensitivity tracer of the Stratosphere-Troposphere Exchange (STE) dynamic processes. The current status of the international research on the application of these nuclides in STE and the difficulties are introduced. The advantages and research basis of Accelerator Mass Spectrometry(AMS) in this respect are summarized. Feasibility analysis and exploration of the key technologies faced by AMS measurement of 7Be and 22Na are presented based on the compact low energy AMS system and the established 10Be measurement method of Tianjin University.
Abstract(0) HTML(0) PDF (1899KB)(0)
Abstract:
Abstract(0) HTML(0) PDF (1767KB)(0)
Abstract:

Column
Display Method:
2021, (2): 1-2.
Abstract(26) HTML(11) PDF (334KB)(9)
Abstract:
2021, 38(2): 117-122.   doi: 10.11804/NuclPhysRev.38.2020084
Abstract(134) HTML(23) PDF (6286KB)(31)
Abstract:
The nucleus 28S (isospin projection $T_{Z}=-2$) near the proton drip-line was produced, separated and purified by HIRFL-RIBLL1 facility and the measurement of $\beta$-delayed $\gamma$ decay of 28S was performed using a detector array consisted of double-sided silicon detectors and Clover-type high purity germanium detectors. Five $\gamma$ transitions from $\beta$ decay of 28S were precisely measured and the corresponding energies of the states of daughter 28P were obtained. The branch ratios of low-lying states of 28P populated by $\beta$ decay were extracted for the first time and the new partial 28S $\beta$-decay scheme was deduced. This work provides accurate data for the further study of mirror asymmetry in 28S/28Mg.
2021, 38(2): 123-128.   doi: 10.11804/NuclPhysRev.38.2021019
Abstract(86) HTML(27) PDF (3153KB)(14)
Abstract:
Neutron star matter is mainly composed of asymmetric dense nuclear matter. At present, there is still great uncertainty in the understanding of the high-density asymmetric nuclear matter through the terrestrial experiments, such as the heavy ion collisions. With the improvement of astronomical observation accuracy and the increase of observable measurements of neutron stars, it is possible to reverse constraint the state of high-density nuclear matter based on astronomical observation of neutron stars. Theoretically investigating the correlation between the observable measurements of neutron stars and the equation of states (EOSs) at different density sections will be helpful to the research of the reverse constraints. In this work, by employing the piecewise polytrope EOSs, the observable measurements of the radius(R), tidal deformability($\varLambda$), moment of inertia(I) of the neutron star $etc$. are calculated and analyzed, and the correlations between these observations and each density segment of the EOSs are given. The results show that tidal deformability ($\varLambda$) and f-mode frequency ($\nu$) of a canonical neutron star ($M \!=\! 1.4\, M_{\odot}$) are mainly correlated with $0.5\rho_{\rm{sat}} \!\sim\! 1.5\rho_{ sat}$, $2.5\rho_{\rm{sat}} \!\sim\! 3.5\rho_{\rm{sat}}$ and $3.5\rho_{\rm{sat}} \!\sim\! 4.5\rho_{\rm{sat}}$ segments of EOSs; the neutron star radius (R) are mainly correlated with $1.5\rho_{\rm{sat}} \!\sim\! 3.5\rho_{\rm{sat}}$ and the crust segments of EOSs; the moment of inertia (I) are mainly correlated with the density below $4.5\rho_{\rm{sat}}$ segments of EOSs.
2021, 38(2): 129-135.   doi: 10.11804/NuclPhysRev.38.2021022
Abstract(83) HTML(22) PDF (4993KB)(10)
Abstract:
Configurations are the basis of lattice QCD calculations. In this paper, we generate a set of configurations with the Wilson clover quark action using the open source software Chroma. The parameters are tuned such that the lattice spacing is ~0.105 fm, pion mass is ~220 MeV. The volume is $32^3 \times 64$. These configurations will be used to study nucleon structure and exotic hadronic states in lattice QCD.
2021, 38(2): 136-146.   doi: 10.11804/NuclPhysRev.38.2021010
Abstract(58) HTML(15) PDF (3775KB)(2)
Abstract:
This paper discusses the finite-volume effect in calculating hadron form factors using lattice QCD framework. Taking Pion as the example, we introduce the method of extracting hadron form factors from three-point correlation functions computed in lattice QCD, but only at separated points in the momentum space because of the finite-volume effect. This paper gives one interpolation algorithm which respects rotation symmetry and also provides a sketch of another interpolation method which applies the continuous Fourier transform, both methods continuously giving form factor results on the momentum space based on the discrete values. These algorithms are examined under numerical models and realistic lattice systems. The results given by the interpolation are independent of specific systems and can be easily generalized to a variety of lattice systems. Our conclusion also provides valuable information which could help determining the proper size of lattice systems.
2021, 38(2): 147-152.   doi: 10.11804/NuclPhysRev.38.2021001
Abstract(59) HTML(18) PDF (3361KB)(15)
Abstract:
The beam energy extracted from cyclotron is fixed, it is necessary to adjust it to meet different demands of different experiments. This study focuses on the feasibility of using thin film materials to change the beam energy. The ranges of 30 MeV α beams (extracted from cyclotron) in materials include diamond, aluminum and copper are calculated by the SRIM program, and the relationship between material thickness and the required beam energy is determined. The horizontal and vertical emittances of α beams, after being reduced to 9 MeV by interacting with different materials, are calculated by G4Beamline program. The following results are obtained: After penetrating the thin film materials, the size of beam spot approximately remained the same. The growth of beam transverse emittances is mainly caused by the increase of the divergence angles, among which the diamond film causes the least increase of beam emittance, and the root mean square value of the divergence angle is about 16 mrad. There is no significant dependency on the value of initial beam divergence angle (the root mean square value of initial divergence angle is less than 1 mrad). Vertical energy spread caused by different materials is about 1 MeV (FWHM) that is only determined by the final beam energy and has no connection with the kind of material. The more energy has lost, the greater the energy spread would be. Besides, the 30 MeV initial α beams interacting with thin film materials (diamond, copper, aluminum etc.) could produce about 109/μA neutrons and γ particles, so radiation protection must be considered in practical applications.
2021, 38(2): 153-158.   doi: 10.11804/NuclPhysRev.38.2020080
Abstract(58) HTML(35) PDF (3216KB)(9)
Abstract:
The BUMP power supply is the key equipment responsible for the beam extraction of the medical heavy ion accelerator. The synchronization of the current rise affects the extraction efficiency of the beam, and the diversity of the current waveform is closely related to the treatment mode and treatment accuracy. It is necessary to generate 1~5 ms rising and accurately synchronized excitation current on the convex rail magnet (0.2~0.4 mH), and ensure the current tracking and the diversity of the waveform. Real-time adjustment of the strong excitation voltage and current waveform based on characteristic parameters are adopted. Control Method. This article introduces the software and hardware design of the digital controller for the BUMP power supply based on Inter's SoC(System-on-a-Chip) technology, and it is applied to the medical heavy ion accelerator device for the first time. After field verification, it is produced on different convex rail magnets. The synchronously changing current of 1~5 ms is achieved, and the tracking accuracy (>5 s) of the current rising period is guaranteed, which meets the design requirements.
2021, 38(2): 159-165.   doi: 10.11804/NuclPhysRev.38.2020074
Abstract(37) HTML(7) PDF (6573KB)(3)
Abstract:
In recent years, ion therapy technology has developed rapidly in China and abroad. To meet the demands of the accelerator commissioning and the energy requirements of the different treatment scheme for the accelerator facility, the power supplies of the dipole magnets in the energy selection and beam transport system are required to work in the modes of DC, in-order trigger and periodic pulse. Using the integrated box controller independently developed by the Institute of Modern Physics, Chinese Academy of Sciences, the control and protection function of the power supply are realized. In order to meet the requirements of commissioning and treatment working modes, the controller has been designed to support the local and remote control network protocols, between which the switch can be achieved through the button on the touch screen. The power supply specifications has been tested after the main circuit and controller were designed and assembled. The test results indicate that the power supply can work well under the different modes, the long-term stability of current rating reached 21 ppm, and the current ripple was less than 0.000 4, exceeding the design index.
2021, 38(2): 166-174.   doi: 10.11804/NuclPhysRev.38.2020064
Abstract(50) HTML(17) PDF (4430KB)(3)
Abstract:
Due to the existence of a large number of nonlinear devices in the accelerator system, a large number of ripples are generated, which seriously affects the control of the accelerator magnetic field on the particle trajectory. In order to realize the suppression of accelerator DC power supply ripple, related researches mainly focused on using voltage-type active power filter to reduce DC power supply ripple, but this method has problems such as insufficient suppression accuracy, response delay, and large switchgear loss. In view of the above problems, this paper compares the main circuit topology of current-type and voltage-type active power filters, investigates the pulse width modulation technology and control strategies of current-type and voltage-type active power filters, and analyzes the performance of different active power filters in the accelerator system to suppress the output current ripple of magnet power supply. Through simulation analysis and experimental verification, it is found that the current-type active power filter has a significant suppression effect on the output current ripple of the magnet power supply, and the current-type active power filter can directly control the output ripple current, and the ripple accuracy is suppressed more highly. With the CSAPF put into use, the load current ripple is significantly reduced, and the current ripple coefficient reaches 1.6×10–5.
2021, 38(2): 175-181.   doi: 10.11804/NuclPhysRev.38.2020063
Abstract(84) HTML(15) PDF (3838KB)(7)
Abstract:
2021, 38(2): 182-189.   doi: 10.11804/NuclPhysRev.38.2020062
Abstract(73) HTML(19) PDF (8245KB)(7)
Abstract:
The Back-n White Neutron Source is located in China Spallation Neutron Source(CSNS). It aims to measure nuclear data under different neutron energies. The neutron’s energy is obtained by the Time Of Flight(TOF) of neutron. In experiment, the time when proton bunches hit the thick tungsten target is considered as the start point of TOF(T0), and the corresponding electronic signal is used to trigger the whole electronic system. The accuracy fan-out of T0 signal will have a significant influence on the accuracy of the TOF measurement and the synchronization of each channel of electronic system. A two-stage accuracy fan-out method of back-n T0 signal is proposed. The T0 signal from CSNS proton accelerator is fanned out by T0 fan-out module to two underground experiment station through long cable. The fan-out module uses signal pre-emphasis technology to improve the signal transmission quality of T0 signal through more than 100 m long cable and guarantee that the T0 signal has a very fast signal leading edge, so as to ensure the accuracy of time timing. The electronic system takes the advantage of the high-performance backplane resources of the chassis by PXIe, so as to realize the global precision and synchronous fan-out of T0 signal. The experimental results show that the leading edge jitter of the T0 signal distributed by the fan-out module reaches 25 ps, the multi-channel accuracy of the chassis reaches 45 ps, and the measurement accuracy of the TOF can reach 248 ps, which meets the requirements of the measurement accuracy of the neutron time of flight of the white light neutron source.
2021, 38(2): 190-195.   doi: 10.11804/NuclPhysRev.38.2020058
Abstract(55) HTML(17) PDF (10365KB)(5)
Abstract:
Since neutron sensitive microchannel plates (nMCP) has high detection efficiency and the spatial resolution, combined with advanced readout electronics it can be a better choice for energy-resolved neutron imaging detectors. Compared with the matrix-doped nMCP, the nMCP based on Atomic Layer Deposition(ALD) has the advantages of less neutron sensitive material consumption and high secondary electron emission coefficient on the inner wall of the channel. Firstly, the typical neutron and gamma signal of natGd-doped nMCP were studied experimentally. Geant4 simulation and theoretical calculation were performed to optimize the pore diameter, wall thickness, bias angle and coating thickness of the coated 10B2O3 nMCP. It was shown that the thermal neutron detection efficiency was about 56% and the spatial resolution was about 22 μm when the coating thickness was 1 μm, the pore diameter was 10 μm, the wall thickness was 1 μm and the bias angle was 3°. The results are of great significance to the geometric parameter design of nMCP used as energy-resolved neutron imaging detectors at CSNS.
2021, 38(2): 196-202.   doi: 10.11804/NuclPhysRev.38.2021003
Abstract(351) HTML(23) PDF (3746KB)(13)
Abstract:
The model of Active-Well Coincidence Counter(AWCC) was established by MCNPX, meanwhile, with two types of induced neutron source (Am-Li and Am-Be), the neutron coincidence count rate of low enriched uranium was simulated, and the comparison of the measurement accuracy between the two simulations was also demonstrated. It was found that the coincidence count rate induced by Am-Be source was lower than that induced by Am-Li source, and the fitting degree of scaled mass curve under Am-Be source was better than that under Am-Li source, the corresponding relative error was also lower than that of under Am-Li source. The relative error range of uranium mass corresponding to the inspection point under Am-Li source is 0.3%~13%. The relative error range under Am-Be source is 0.1%~4.5%. According to the results, for the measurement of the mass of low enriched uranium by AWCC, it could be better to choose Am-Be source for reducing measurement relative error.
2021, 38(2): 203-209.   doi: 10.11804/NuclPhysRev.38.2020052
Abstract(62) HTML(22) PDF (8583KB)(9)
Abstract:
The irradiation hardening and embrittlement behavior of three kinds of Oxide Dispersion Strengthened(ODS) steel (MA956, 16Cr-4Al, 16Cr-0.1Ti) are investigated by using the HIRFL(Heavy Ion Research Facility in Lanzhou). The main motivation is to find the relation between diameter and density of the oxides and irradiation hardening/embrittlement behavior of different ODS steels. These three kind of materials are irradiated by Ne and Ni ions, and get a uniform damage layer by using the energy degrader. The Nano-hardness and elongation of the materials are obtained by Nano-indentation and small punch test. The sink strength was calculated with the mean diameter and density of the materials. Then followed by nano-indentation test and small punch test to get the irradiation hardening and ductility loss. Results show that irradiation resistance of the materials rise with sink strength(S) increasing.
2021, 38(2): 210-214.   doi: 10.11804/NuclPhysRev.38.2021007
Abstract(40) HTML(21) PDF (2906KB)(14)
Abstract:
The Bohr-Lindhard (B-L) model is used to describe the classical electron-capture process. The impact-parameter dependence of the capture probability is derived by considering the impact-parameter dependence of the collision time between ion and atom. This model limits the impact parameter to be less than the capture radius. In the framework of the B-L model, although the contribution from all impact parameters may be studied through the spatial distribution function of electrons, the multiple numerical integral has to be carried out. In this work, it is proposed that the impact-parameter dependence of the electron-capture probability can be given by a simple exponential decay function based on the (B-L) model. Electron-capture cross sections for Aq+(q=2~6)-H collisions, and double-electron-capture cross sections for Aq+(q=3~6)-He collisions are calculated at low and intermediate velocities. The calculated results are in good agreement with the existing experimental data. The energy and charge-state dependences of the electron-capture process are well described. This work can also be used to calculate the cross sections of electron capture from He and H targets by other ions with different charge states.
2021, 38(2): 215-220.   doi: 10.11804/NuclPhysRev.38.2020066
Abstract(59) HTML(19) PDF (3772KB)(11)
Abstract:
In heavy-ion cancer therapy, Compton camera is a promising tool for online monitoring of the range of ions. Compton camera uses crystal detectors to determine the positions and deposited energies of the $\gamma$-rays. This will further introduce the errors and affect the actual imaging resolution of the Compton camera, due to the involved Doppler broadening effects influencing the image resolution. This work simulates the angular resolution measure originating from the Doppler broadening effects with Geant4 toolkit for 150 and 511 keV gamma, respectively, in different crystal materials. After optimizing the back-projection algorithm and improving the voxel in imaging interspace, the image resolution can be achieved better than 1.0 mm. An approximate formula is also being proposed to evaluate the image resolution based on the angular resolution measure.
2021, 38(2): 221-228.   doi: 10.11804/NuclPhysRev.38.2020075
Abstract(58) HTML(16) PDF (3616KB)(13)
Abstract:
Based on the influence "hydrogen bubbles" and "helium bubbles", which are produced by the neutron induced reactions on Fe, of the new nuclear energy utilization system, the 56,54Fe(n, α)53,51Cr, 56,54Fe(n, p)56,54Mn cross sections are calculated in this work. The physical model (including energy level density, Correction, nuclear temperature, optical potential parameters, etc.) parameters were adjusted according to the existing experimental data and evaluation data of 56,54Fe(n, α)53,51Cr, 56,54Fe(n, p)56,54Mn cross sections, and a set of universal parameters were obtained. Based on the adjusted parameters, the TALYS program is used for calculating 56,54Fe(n, α)53,51Cr, 56,54Fe(n, p)56,54Mn reaction datas, including energy differential cross section and double differential cross section. Furthermore, the results are all in good agreement with the experimental data and evaluation data in the region of incident neutron energy from 0 to 175 MeV. By obtaining the universal parameters, new method was added to our nuclear reaction theory and laid the foundation for the nuclear data evaluation.