Timing system of HIRFL-CSR

The national science project HIRFL-CSR has recently been officially accepted. As a cyclotron and synchrotron complex, it puts some particularly high demands on the control system. There are hundreds of pieces of equipment that need to be synchronized. An integrated timing control system is built to meet these demands. The output rate and the accuracy of the controller are 16 bit/μs. The accuracy of the time delay reaches 40 ns. The timing control system is based on a typical event distribution system, which adopts the new event generation and the distribution scheme. The scheme of the timing control system with innovation points, the architecture and the implemented method are presented in the paper.     

加速器质谱14C断代

着重介绍加速器质谱计（ＡＭＳ）１４Ｃ断代方法,北京大学近三年来ＡＭＳ１４Ｃ断代工作,还介绍了夏商周断代工程及其ＡＭＳ１４Ｃ断代工作.The method of accelerator mass spectrometry (AMS) 14 C dating, some AMS 14 C dating work in Peking University during the recent three years and the project of Xia Shang Zhou chronology are introduced.     

加速器质谱方法测量41Ca及其在生物医学中的应用

介绍了用AMS测量41Ca的方法及其在生物医学中的应用,以及中国原子能科学研究院目前开展4 1Ca的AMS测量及其应用研究的情况.Ca(T 1/2 =1.0×10 5 a) as a tracer, confined with Accelerator Mass Spectrometry (AMS) method and its applications are reviewed. Measurement of 41 Ca with HI-13 tandem AMS system at the China Institute of Atomic Energy is also introduced. The measurement of 41 Ca used for studying mechanism of cancer caused by carcinogenic substances and mechanism of Ca supplement in human body diseases are being developed in collaboration with Department of Occupational Health, Beijing Universit...     

Physics design for the C-ADS main linac based on two dif f erent injector design schemes

The China ADS（C-ADS） project proposes to build a 1000 MW Accelerator Driven sub-critical System around 2032. The accelerator will work in CW mode with 10 mA in beam current and 1.5 GeV in final beam energy. The linac is composed of two major sections： the injector section and the main linac section. There are two diferent schemes for the injector section. The Injector-scheme is based on a 325 MHz RFQ and superconducting spoke cavities of the same RF frequency and the Injector-scheme is based on a 162.5 MHz RFQ and superconducting HWR cavities of the same frequency. The main linac design will be diferent for diferent injector choices. The two diferent designs for the main linac have been studied according to the beam characteristics from the diferent injector schemes.     

Application of ^41Ca Tracer and Its AMS Measurement in CIAE

The man-made calcium isotope ^41Ca is an ideal tracer for the study of calcium metabolism. We represent the first application of accelerator mass spectrometry (AMS) measurement of ^41Ca tracer in China. The technique is being applied to the research field of cell messenger at the China Institute of Atomic Energy (CLAE). The sample preparation methods and the AMS measurements are discussed and some interesting results are presented.     

236U及其加速器质谱（AMS）测量

236U是一种长寿命放射性核素, 其半衰期为T_1/2=2.342(3)×107 a, 在自然界的含量极微, 天然铀中 236U/238U的原子比约为～10-14。 目前, 对于236U及其测量的研究报道较少。首先介绍了236U的产生, 并对地球中 236U的总量进行了估算。 概述了236U测定在亿年级中子注量率积分评估、 核环境和核活动监测, 以及地质学等领域中的重要应用。 最后,对国内外加速器质谱（AMS）测量236U的状况进行了综述,报道了中国原子能科学研究院AMS小组通过对同位素干扰鉴别的多方面研究, 初步建立了236UAMS测量方法。 236U is a longlived radionuclide with half life of 2.342(3)×107 a. The ratio of 236U/238U is about 10-14 in the natural Uranium. The origin and production of 236U in globe are introduced and estimated in this paper,respectively. The major applicationsion of 236U as a 100 million year neutron flux integrator,as a “fingerprint” for monitoring nuclear environment and nuclear activity,and as a tracer in geological studies are briefly summarized. The accelerator mass spectrometry(AMS) measurement of 236U in the world and the research on HI 13 tandem accelerator at China Institute of Atomic Energy(CIAE) is also mentioned in this paper.     

Full period superconducting section physics design for injector Ⅱ of China-ADS

The China Accelerator Driven Subcritical System （China-ADS） project, which is a strategic plan and aims to design and build an ADS demonstration facility, has been proposed and launched actively in China. Injector Ⅱ as one of the parallel injectors of China-ADS, and is prompted by the Institute of Modern Physics （IMP）. In this paper, a new scheme with full period lattice structure for the SC section is proposed. In the new scheme, there are sixteen periods, with one superconducting solenoid and one superconducting cavity included in each period. All of the elements are contained in four eryomodules. The dreadful influence of the mismatch caused by period structural change can be avoided, and the beam quality is favorable. In addition, this new scheme has certain advantages in reducing the project＇s difficulty and construction risk. The details of the design and beam dynamic simulation for the full period lattice structure are given in this paper.     

加速器质谱在核科学研究中的应用进展

加速器质谱(AMS) 由于其极高的测量灵敏度而广泛应用于核科学、生命科学、地球科学、环境科学和考古学等研究领域,同时,AMS还可以用来分析样品中的微量核素,是核科学领域的重要研究工具。目前,AMS研究的最新领域是U和Pu 等锕系元素的测量,在核保障、核监测及核试验沉降物示踪大气输运和表面沉积物的迁移等研究中也显示出了较大潜力。综述了AMS在核科学研究中的应用及研究现状,主要包括AMS在放射性核素半衰期的测定、核反应截面的测量等方面的研究进展。Accelerator mass spectrometry (AMS) is a promising method to provide extreme sensitivity measurements of the production yields of long-lived radioisotopes, which cannot be detected by other methods. AMS technique plays an important role in the research of nuclear physics, as well as the application field of AMS covered nuclear science and technology, life science, earth science, environmental science, archaeology etc. The newest AMS field is that of actinide, particularly U and Pu, isotopic assay with expanding applications in nuclear safeguards and monitoring, and as a modern bomb-fallout tracer for atmospheric transport and surface sediment movement. This paper reviews the applications of AMS in the research of nuclear energy and nuclear security including the research of half life of radionuclides, cross section of nuclear reaction.     

BEPCII Injector Linac Upgrade and Beam Instabilities

The upgrade project of the Beijing Electron Positron Collider （BEPCII） and its injector linac is working well. The linac upgrade aims at a higher injection rate of 5OmA/min into the storage ring, which requires an injected beam with low emittance, low energy spread and high beam orbit and energy stabilities. This goal is finally reached recently by upgrading the linac components and by dealing with rich and practical beam physics, which are described in this study.     

Determination of the number of atoms of the long-lived nuclide 126Sn by γ-ray spectrometry

By using HPGe γ-ray spectrometry, the activity of the long-lived fission product 126Sn in a SnOB2 sample was measured. The number of 126Sn atoms and the ratio of 126Sn to Sn were calculated based on the half-life value of 2.35×105a and the chemical stoichiometry. The result of the ratio of 126Sn to Sn, （1.033±0.037）×10-8, is consistent with the results measured by the accelerator mass spectrometry （AMS） within uncertainty limits, which confirms our procedures in the measurement of 126Sn by AMS and lays a foundation for the AMS measurement of 126Sn at much lower levels.     

加速器质谱及其小型化技术

加速器质谱(AMS)是迄今测量长寿命放射性核素灵敏度最高的分析技术,在考古、地质、环境、物理等领域得到了较为广泛的应用.随着技术的不断改进,AMS装置亦朝着小型化方向发展,并也得到了很好应用.对AMS所具有的长寿命放射性核素高灵敏分析能力的关键技术进行了综合论述,并针对小型化AMS系统所采用的特色技术进行了系统介绍.最...     

AMS测量中同量异位素的鉴别方法

在加速器质谱测量中,存在同位素和同量异位素的干扰.排除同位素的干扰是开展超微量核素分析的重要课题之一.主要介绍了加速器质谱测量中同量异位素的几种鉴别、排除方法,以及这些方法的原理、发展及应用. There are interference of isotopes and isobars in accelerator mass spectrometry (AMS) measurements. Eliminating the isobaric interference is the important aspect in AMS measurements. Several methods of isobaric identification in AMS measurements are discussed in this paper. Principles, developments and applications of these methods are also introduced.     

加速器质谱测量53Mn及其在地球科学中的应用

宇宙成因核素 53Mn是一种非常理想的地貌演变研究工具。近年来, 随着加速器质谱（AMS）技术的不断发展, 人们已能够进行53Mn的高灵敏测量。介绍了53Mn在地球科学中的应用前景、 国际研究现状及中国原子能科学研究院目前正在开展的53Mn高灵敏AMS测量方法的研究。The determination of cosmogenic 53Mn concentrations found in terrestrial formations has many interesting applications for Earth Sciences. With Accelerator Mass Spectrometry (AMS) it should be possible to detect minute amounts of 53Mn. The situation of international research of 53Mn AMS measurement and applications are presented. The AMS measurement method of 53Mn at China Institute of Atomic Energy and its applications prospect are to be explored.     

~(36)Cl的加速器质谱测量及其应用

长寿命核素36Cl的半衰期为3.01×105a,广泛分布于自然界中。加速器质谱是目前测量36Cl的最灵敏的方法。介绍了36Cl的样品制备及加速器质谱测量方法,重点描述了基于小型化加速器质谱发展起来的测量36Cl的探测方法及其特点,综述了各实验室利用36Cl在相关领域开展的工作及所取得的成果。     

A small and compact AMS facility for tritium depth profiling

Depth profiling measurements of tritium in carbon samples have been performed during the past seven years at the AMS facility installed at the Rossendorf 3 MV Tandetron. The samples have been cut from the inner walls of the fusion experiments ASDEX-upgrade/Garching and JET/Culham. The tritium content of the samples from JET required a dedicated AMS facility to prevent any contamination of the versatile 3 MV Tandetron. On the basis of an air-insulated 100 kV tandem accelerator equipped with a gas stripper an AMS facility exclusively devoted to tritium depth profiling was installed, tested and used for routine measurements. After additional successful tests employing diamond-like carbon (DLC) stripper foils at this accelerator, another small and compact 100 kV tandem accelerator with SF₆ insulation and a DLC stripper has been installed at the AMS facility. Results obtained with the different tandem accelerators are presented.     

AMS重核素测量的入射离子X射线探测法

介绍了在加速器质谱学中发展的入射离子 X射线的探测技术,以便应用于测定中重同位素的同量异位素鉴别 .描述了在中国原子能科学研究院加速器质谱计上建立的入射离子 X射线探测装置和实验结果 .通过测量入射离子 X射线,实现了64Cu测量中对同量异位素64Ni和64Zn的鉴别 ,以及79Se测量中对79Br的鉴别. In recent years, a new technique to detect the charteristic X ray from projectile ions in accelerator mass spectrometry (AMS) has been developed. After analysis in the routine AMS system, the ions are stopped in an appropriately chosen target in steat of an ion detector and induced X ray are detected for identification of ions by atomic number. For the application of AMS to higher mass isotopes with mass number>20 using small accelerator, the characteristic X rays technique is better...     

宇生核素10Be、7Be、22Na大气示踪概述

大气宇宙成因核素10Be、7Be、22Na作为平流层、对流层之间物质交换(STE)动力学过程的敏感示踪剂,对于全球气候变化、大气环境治理等研究具有非常重要的意义.介绍了这几种核素应用于STE的国际研究现状以及面临的困难,概述了加速器质谱法(AMS)在此方面具备的优势和研究基础,基于天津大学的小型低能量AMS系统和已建立...     

小型加速器质谱系统研制及分析技术研究

加速器质谱(AMS)是测量长寿命放射性核素灵敏度最高的分析技术,在环境、地质、考古、物理等领域有着广泛应用。近年来,AMS装置的小型化在国际上得到了很大发展。为了研发小型化AMS装置及其分析技术,中国原子能科学研究院分别自主研制了加速电压为0.2 MV的单极型AMS装置和端电压为0.3 MV的串列型AMS装置。基于研制的单极型AMS装置,成功开展了14C的高效传输和本底排除技术研究,实现了14C的高灵敏测定,14C/12C的测量灵敏度达到2×10–15;利用研制的串列型AMS装置,开展了低能量下129I的气体剥离条件、本底排除和探测方法研究,建立了129I的高效传输和高灵敏测量方法,129I/127I的测量灵敏度为1×10–14。这是国内首次研制成功小型AMS装置,为AMS国产化奠定基础。