检索结果-南通市图书馆

Chinese Physics Letters 2021年第9期38卷 38-42页

作者： Chuyi Huang Junpei Zhang Fan Ye Zecong Qin Syed Mohd Amir Zachary Norris Buck Ahmed Salman Wolfgang Kreuzpaintner Xin Qi Tianhao Wang Xin Tong Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China spallation neutron source science center Dongguan 523803China

Polarized 3He neutron spin filters(NSFs)can be used as a vital tool for neutron polarization production and *** China spallation neutron source(CSNS),as one of the major neutron facilities in China,has committed resources to the development of a polarized ^(3)He NSF program to support its growing polarized neutron research.A spin-exchange optical pumping(SEOP)-based polarized ^(3)He system and other necessary hardware for NSF transport has been recently *** performance of the system is benchmarked using an in-house developed cell named“Trident”.neutron beam measurements yield a ^(3)He polarization of 77%with over 200 h of on-beam relaxation *** this newly developed SEOP system with the recently reported cell fabrication station,CSNS is now capable of the fully self-sustained production of ^(3)He NSFs that shall support its future neutron polarization research.

关键词： polarized system relaxation

Measurement of the relative neutron sensitivity curve of a LaBr_(3)(Ce)scintillator based on the CSNS Back-n white neutron source

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2023年第10期32卷 66-72页

作者：刘建王东明甫跃成李忠宝易晗易龙涛 Institute of Nuclear Physics and Chemistry China Academy of Engineering PhysicsMianyang 621900China spallation neutron source science center Dongguan 523803China

A scintillator detector consisting of a LaBr_(3)(Ce)(0.5%)scintillator,a photomultiplier tube(PMT),and an oscilloscope were used to study the neutron sensitivities of the LaBr_(3)(Ce)scintillator at the China spallation neutron source(CSNS)Back-n white neutron source in the double-bunch and single-bunch operation modes,*** the two operational modes,the relative neutron sensitivity curves of the LaBr_(3)(Ce)scintillator in the energy regions of 1–20 MeV and 0.5–20 MeV were obtained for the first *** the energy range of 1–20 MeV,the two curves were nearly *** the relative neutron sensitivity uncertainties of the double-bunch experiment were higher than those of the single-bunch *** above results indicated that the single-bunch experiment's neutron sensitivity curve has a lower minimum measurable energy than the double-bunch *** the minimum measurable energy of the double-bunch experiment,there is little difference between the measured relative neutron sensitivity curves of the single-bunch and double-bunch experiments of the LaBr_(3)(Ce)scintillator and those of other scintillators with a similar neutron response signal intensity.

关键词： relative neutron sensitivity LaBr_(3)(Ce) China spallation neutron source(CSNS) white neutron source

Design of nanosecond edge and high-frequency bipolar beam chopper pulse power supply for CSNS

在线全文

学校读者我要写书评

暂无评论

Radiation Detection Technology and Methods 2024年第2期8卷 1229-1238页

作者： Haibo Li Xin Qi Huafu Ouyang Wenqing Zhang Peng Zhu Munan Lin Yuntao Liu Guodong Zhao Jun Li Yuan Huang Institute of High Energy Physics BeijingChina spallation neutron source science center Dongguan523803China

Background The beam chopper system of China spallation neutron source(CSNS)is used to pulsed chop the negative hydrogen ion beam from ion source;in order to meet the beam time structure of rapid cycling synchrotron(RCS),it is the key to control emittance growth of low energy beam and decrease beam loss during the beam injection process from the linac to *** beam chopped,the particle beam is required to deviate completely and then lose at entrance of radiofrequency quadrupole(RFQ)cavity;considering high duty cycle of ion source and beam high chop rate,the effect of deflected particles on RFQ is difficult to *** A bipolar beam chopper pulse power supply is developed,which makes the beam spot at the entrance of RFQ twice that of unipolar beam chopper power supply,and reduces the damage of deflected particles to RFQ cavity and *** The beam chopper power supply provides a fast high voltage pulse source;two fast reversing switches are used to quickly change the polarity of the output high voltage pulse in 40 *** and conclusion The power supply has been installed in the low beam energy transport line(LEBT),the output high voltage pulse is±6 kV,frequency is about 1 MHz,and the pulse edge is less than 10 ns.

关键词： CSNS LEBT Beam chopper system Bipolar beam chopper Power supply

Development of a large nanocrystalline soft magnetic alloy core with highμ'_(p)Qf products for CSNS-Ⅱ

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nuclear science and Techniques 2022年第8期33卷 45-54页

作者： Bin Wu Xiao Li Zhun Li Chun-Lin Zhang Yang Liu Wei Long Xiang Li Jian Wu Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China spallation neutron source science center Dongguan 523803China University of Chinese Academy of sciences Beijing 100049China

A waterproof nanocrystalline soft magnetic alloy core with a size of O.D.850 mm×I.D.316 mm×H.25 mm for radio frequency acceleration was successfully developed by winding 18μm 1k107b MA ***μ'_(p)Qf products reached 7.5,10,and 12 GHz at 1,3,and 5 MHz,***μ'_(p)Qf products of the MA core(O.D.250 mm×I.D.100 mm×H.25 mm)manufactured using a 13μm MA ribbon further increased by 30%.Detailed improvements on the MA core manufacture process are discussed *** high-power tests on the new MA cores demonstrated its good performance of waterproofness,particularly its stability of highμ'_(p)Qf *** MA core with highμ'pQf product and large size can operate under a high average RF power,high electric field,and in deionized water,which will be used in the China spallation neutron source PhaseⅡ(CSNS-Ⅱ).

关键词： Large size magnetic alloy core High insulation and low stress coating Waterproof structure Transverse magnetic field annealing High power MA-loaded cavity

Large area^(3)He tube array detector with modular design for multi‑physics instrument at CSNS

在线全文

学校读者我要写书评

暂无评论

Nuclear science and Techniques 2023年第1期34卷 1-12页

作者： Lin Zhu Jian‑Rong Zhou Yuan‑Guang Xia Liang Xiao Hong Luo Xiao‑Juan Zhou Wen‑Qin Yang Bei‑Ju Guan Xing‑Fen Jiang Yan‑Feng Wang Hong Xu Hai‑Yun Teng Li‑Xin Zeng Jia‑Jie Li Lei Hu Ke Zhou Yong‑Xiang Qiu Pei‑Xun Shen Jun Xu Li‑Jiang Liao Xiao‑Zhuang Wang Gui‑An Yang Huai‑Chan Chen Ju‑Ping Xu Zhi‑Duo Li Song‑Lin Wang Jian Zhuang Yu‑Bin Zhao Jun‑Rong Zhang Wen Yin Zhi‑Jia Sun Yuan‑Bo Chen Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China spallation neutron source science center Dongguan 523803China University of Chinese Academy of sciences Beijing 100049China

The multi-physics instrument(MPI)is the first user cooperative instrument at the China spallation neutron source(CSNS).It was designed to explore the structures of complex materials at multiple scales based on the neutron total scattering *** imposes the requirements for the detector,including a high detection efficiency to reduce the measurement time and a large solid angle coverage to cover a wide range of momentum *** satisfy these demands,a large-area array of 3He-filled linear position-sensitive detectors(LPSDs)was constructed,each with a diameter of 1 inch and pressure of 20 *** uses an orbicular layout of the detector and an eight-pack module design for the arrangement of 3He LPSDs,covering a range of scattering angles from 3°to 170°with a total detector area of approximately 7 *** detector works in air,which is separated from the vacuum environment to facilitate installation and *** characteristics of the MPI detector were investigated through Monte Carlo(MC)simulations using Geant4 and experimental *** results suggest that the detectors are highly efficient in the wavelength range of the MPI,and an efficiency over 25%is achievable for above 0.1 A neutrons.A minimal position resolution of 6.4 mm full width at half maximum(FWHM)along the tube length was achieved at a working voltage of 2200 V,and a deviation below 2 mm between the real and measured positions was attained in the beam *** detector module exhibited good consistency and an excellent counting rate capacity of up to 80 kHz,which satisfied the requirements of experiments with a high event *** of its operation over the past year have shown that the detector works steadily in sample experiments,which allows the MPI to serve the user program successfully.

关键词： neutron detector LPSD Position resolution Counting rate capacity

Design and commissioning of a wideband RF system for CSNS-Ⅱ rapid-cycling synchrotron

在线全文

学校读者我要写书评

暂无评论

Nuclear science and Techniques 2024年第1期35卷 35-44页

作者： Jian Wu Xiang Li Bin Wu Chun-Lin Zhang Yang Liu Wei Long Xiao Li University of Chinese Academy of sciences Beijing 100049China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China spallation neutron source science center Dongguan 523803China

The China spallation neutron source(CSNS) upgrade project(CSNS-Ⅱ) aims to enhance the beam power from 100 to 500 kW. A dual-harmonic accelerating method has been adopted to alleviate the stronger space-charge effect in rapid-cycling synchrotrons owing to the increased beam intensity. To satisfy the requirements of dual-harmonic acceleration, a new radiofrequency(RF) system based on a magnetic alloy-loaded cavity is proposed. This paper presents design considerations and experimental results regarding the performance evaluation of the proposed RF system through high-power tests and beam commissioning. The test results demonstrate that the RF system satisfies the desired specifications and affords significant benefits for CSNS-Ⅱ.

关键词： Dual-harmonic acceleration Magnetic alloy-loaded cavity RF system

Feasibility of medical radioisotope production based on the proton beams at China spallation neutron source

在线全文

学校读者我要写书评

暂无评论

Nuclear science and Techniques 2024年第6期35卷 26-39页

作者： Bing Jiang Bin-Bin Tian Han-Tao Jing Qi-Fan Dong spallation neutron source science center Dongguan 523803China Institute of High Energy Physics Chinese Academy of Sciences(CAS)Beijing 100049China University of Chinese Academy of sciences Beijing 100049China

The utilization of a proton beam from the China spallation neutron source(CSNS)for producing medical radioisotopes is appealing owing to its high current intensity and high *** medical isotope production based on the proton beam at the CSNS is significant for the development of future radiopharmaceuticals,particularly for theα-emitting *** production yield and activity of typical medical isotopes were estimated using the FLUKA *** results indicate that the 300-MeV proton beam with a power of 100 kW at CSNS-II is highly suitable for proof-of-principle studies of most medical *** particular,this proton beam offers tremendous advantages for the large-scale production of alpha radioisotopes,such as 225Ac,whose theoretical production yield can reach approximately 57 Ci/*** on these results,we provide perspectives on the use of CSNS proton beams to produce radioisotopes for medical applications.

关键词： CSNS proton beam Medical isotope production α-Emitting radionuclides Nuclidic purity analysis

Topological Confinement in Reversibly Interlocked Polymer Networks

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer science 2024年第2期42卷 133-140,I0004页

作者： Wan-Ting Dai Zhen-Hua Xie Yu-Bin Ke Yang You Min-Zhi Rong Ming-Qiu Zhang Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education GD HPPC LabIGCMESchool of ChemistrySun Yat-sen UniversityGuangzhou510275China spallation neutron source science center China Spallation Neutron SourceDongguan523803China Institute of High Energy Physics Chinese Academy of SciencesBeijing100049China College of Materials and Metallurgy Guizhou UniversityGuiyang550025China

Recently, we reported a series of reversibly interlocked polymer networks(RILNs), whose mechanical robustness and functionalities improvement was believed to be derived from topological interlocking of two sub-networks, although the direct evidence for the deduction is still lacking. Herein, a specially-designed RILNs system, in which the inter-component hydrogen bonds can be shielded as needed, was prepared and used to study the micro-structures of RILNs, aiming to verify the existence of mechanical interlocking in RILNs. By changing the pH of the swelling solvent, the effect exerted by the inter-component non-covalent bonds was eliminated, so detailed information of the networks structure was exposed. The small angle X-ray scattering(SAXS) and small-angle neutron scattering(SANS) results indicated that swelling-induced structural evolution of the two sub-networks mutually affected each other, even when the inter-component hydrogen bonds were absent, proving the presence of topological interlocking. The findings may help to draw a more accurate physical image and reveal the detailed structureproperty relationship of RILNs.

关键词： Reversibly interlocked polymer networks Small angle X-ray scattering Small-angle neutron scattering Topological confinement

Design and performance of the LLRF control system for CSNS linac

在线全文

学校读者我要写书评

暂无评论

Radiation Detection Technology and Methods 2020年第2期4卷 196-202页

作者： Linyan Rong Zhencheng Mu Jian Li Zhexin Xie Wenzhong Zhou Bo Wang Maliang Wan Meifei Liu Xinan Xu Institute of High Energy Physics Chinese Academy of SciencesBeijingChina spallation neutron source science center DongguanChina

Objective The China spallation neutron source(CSNS)linac is designed with beam energy of 80 MeV and a peak current of 15 mA in the first *** consists of RFQ,two bunchers of medium-energy beam transmission line,four DTL tanks and one debuncher of linac-to-ring beam transmission ***,eight online RF power sources are used to power these *** order to stabilize the amplitude,phase and resonant frequency of the RF accelerating field,and minimize beam loss,we have established digital low-level RF(LLRF)control *** The LLRF system includes RF reference line,analog module(AM),clock distribution module,digital control module(DCM),high-power protection module,timing and RF interlock module and so *** DCM is mainly responsible for the stability of the RF field amplitude and phase,and RF interlock module can quickly cut off the RF drive in case of arc in the RF transmission system,VSWR over threshold or cavity vacuum fault and so *** During beam commissioning,all of eight online units of LLRF control system were operating stably and *** amplitude and phase variations of the linac fields have been achieved about±0.4%and±0.15°with 10-mA beam loading,much better than the design requirements of±1%in amplitude and±1°in *** With the help of this system,we achieved stable operation under different beam ***,many important progresses have been achieved in the LLRF control system for amore convenient operation and a higher stability *** article describes the design and implementation of the LLRF for CSNS linac.

关键词： RF power source LLRF Reference system High-power protection Tracking resonant frequency of cavity

Mechanical design of a low β superconducting elliptical cavity for CSNS-II

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Radiation Detection Technology and Methods 2021年第3期5卷 315-323页

作者： Peihua Qu Huachang Liu Yun Wang Bo Li Xiaolei Wu Ahong Li Mengxu Fan Qiang Chen Jun Peng Institute of High Energy Physics Chinese Academy of Sciences(CAS)Beijing 100049China spallation neutron source science center Dongguan 523803China

Background A lowβsuperconducting elliptical cavity was designed for the China spallation neutron source phase II project(CSNS-II).Methods The method to improve the mechanical stability of the lowβsuperconducting elliptical cavity was introduced,and the corresponding mechanical design was *** software COMSOL Multiphysics and ANSYS APDL were used to calculate the static Lorentz force detuning factor k_(L)(LFD)and the helium pressure sensitivity factor k_(p)(DFDP)of the bare cavity,which were−4.71 Hz(MV/m)^(−2) and−21.1 Hz/mbar,*** double-ring stiffeners reinforcement scheme was *** The radii of the double-ring stiffeners were 70 and 135 mm,*** structure design of the helium vessel of the cavity was *** following is the mechanical parameters of the reinforced cavity,the tuning sensitivity is 199.8 kHz/mm,longitudinal stiffness is 4.76kN/mm,k_(L) and k_(p) were−1.39 Hz(MV/m)^(−2) and 4.67 Hz/mbar,respectively,which met the operating *** tuning sensitivity and stiffness of the reinforced cavity with different wall thicknesses were optimized,and the final wall thickness was selected as 4 *** The mechanical design of CSNS-II 648 MHz five-cell lowβsuperconducting elliptical cavity was introduced systematically in the *** LFD,DFDP,and the maximum surface stress of the cavity were reduced by optimizing the cavity wall thickness and the position of the double-ring *** reinforced cavity met operational requirements.

关键词： Lowβsuperconducting elliptical cavity Mechanical design LFD DFDP Tuning sensitivity Longitudinal stiffness