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Stepped-up development of accelerator mass spectrometry method for the detection of ^(60)Fe with the HI-13 tandem accelerator

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Nuclear Science and Techniques 2024年第4期35卷 136-143页

作者： Yang zhang Sheng-Quan Yan Ming He Qing-zhang Zhao Wen-hui zhang Chao-Xin Kan jian-Ming Zhou Kang-ning Li xiao-Fei wang jian-Cheng Liu Zhao-Hua peng Zhuo Liang Ai-Ling Li jian Zheng Qi-Wen Fan Yun-Ju Li You-Bao wang Zhi-Hong Li Yang-Ping Shen ding Nan Wei Nan Yu-Qiang zhang Jia-Ying-Hao Li Jun-Wen Tian jiang-Lin Hou Chang-Xin Guo Zhi-Cheng zhang Ming-Hao Zhu Yu-Wen Chen Yu-Chen jiang Tao Tian Jin-Long Ma Yi-hui Liu Jing-Yu Dong Run-Long Liu Mei-Yue-Nan Ma Yong-Shou Chen Wei-Ping Liu Bing Guo China Institute of Atomic Energy P.O.Box 275(10)Beijing 102413China College of Science Southern University of Science and TechnologyShenzhen 518055China School of Physics Xi’an Jiaotong UniversityXi’an 710049China

The Moon provides a unique environment for investigating nearby astrophysical events such as *** samples retain valuable information from these events,via detectable long-lived“fingerprint”radionuclides such as^(60)*** this work,we stepped up the development of an accelerator mass spectrometry(AMS)method for detecting^(60)Fe using the HI-13tandem accelerator at the China Institute of Atomic Energy(CIAE).Since interferences could not be sufficiently removed solely with the existing magnetic systems of the tandem accelerator and the following Q3D magnetic spectrograph,a Wien filter with a maximum voltage of±60 kV and a maximum magnetic field of 0.3 T was installed after the accelerator magnetic systems to lower the detection background for the low abundance nuclide^(60)Fe.A 1μm thick Si_(3)N_(4) foil was installed in front of the Q3D as an energy *** particle detection,a multi-anode gas ionization chamber was mounted at the center of the focal plane of the ***,an^(60)Fe sample with an abundance of 1.125×10^(-10)was used to test the new AMS *** results indicate that^(60)Fe can be clearly distinguished from the isobar^(60)*** sensitivity was assessed to be better than 4.3×10^(-14)based on blank sample measurements lasting 5.8 h,and the sensitivity could,in principle,be expected to be approximately 2.5×10^(-15)when the data were accumulated for 100 h,which is feasible for future lunar sample measurements because the main contaminants were sufficiently separated.

关键词： Accelerator mass spectrometry Wien filter Isobar separation Supernovae Chang'e-5 lunar samples

A New Type of Conserved Quantity of Mei Symmetry for Lagrange Systems

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Communications in Theoretical Physics 2007年第5X期48卷 799-800页

作者： ding ning fang jian-hui wang peng zhang xiao-ni College of Physics Science and Technology China University of Petroleum Dongying 257061 China

A new type of conserved quantity, which is induced from the Mei symmetry of Lagrange systems, is studied. The conditions for that the new type of conserved quantity exists and the form of the new type of conserved quantity are obtained. An illustrated example is given. The Noether conserved quantity induced from the Mei symmetry of Lagrange systems is a special case of the new type of conserved quantity given in this paper.

关键词： Mei symmetry new type of conserved quantity Lagrange system

Perturbation to Lie Symmetry and Lutzky Adiabatic Invariants for Lagrange Systems

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Communications in Theoretical Physics 2008年第1期49卷 57-60页

作者： ding ning fang jian-hui wang peng zhang xiao-ni College of Physics Science and Technology China University of Petroleum Dongying 2570617 China

Based on the concept of adiabatic invariant, perturbation to Lie symmetry and Lutzky adiabatic invariants for Lagrange systems are studied by using different methods from those of previous works. Exact invariants induced from Lie symmetry of the system without perturbation are given. Perturbation to Lie symmetry is discussed and Lutzky adiabatic invariants of the system subject to perturbation are obtained.

关键词： symmetry perturbation Lutzky adiabatic invariant Lagrange system

Perturbation to Lie Symmetry and Hojman Exact and Adiabatic Invariants of Generalized Raitzin Canonical Equation of Motion

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Communications in Theoretical Physics 2007年第4X期48卷 615-618页

作者： wang peng fang jian-hui ding ning zhang xiao-ni College of Physics and Technology China University of Petroleum Dongying 257061 China

In this paper, firstly, we get the Hojman exact invariants by Lie symmetry for an undisturbed generalized Raitzin equation of motion. Secondly, we study the perturbation to Lie symmetry of generalized Raitzin canonical equation of motion and get Hojman adiabatic invariants. Lastly, an example is given to illustrate the application of the results.

关键词： generalized mechanics symmetry Raitzin canonical equation perturbation adiabatic invariant

A Unified Symmetry of Mechanical Systems with Variable Mass in Phase Space

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Communications in Theoretical Physics 2006年第3X期46卷 385-388页

作者： wang peng fang jian-hui zhang peng-Yu, ding ning College of Physics and Technology China University of Petroleum Dongying 257061 China

In this paper, the definition and the criterion of a unified symmetry of the mechanical system with variable mass in phase space are given. The Noether conserved quantity, the generalized Hojman conserved quantity, and Mei conserved quantity deduced from the unified symmetry are obtained. An example is given to illustrate the application of the results.

关键词： phase space variable mass system unified symmetry conserved quantity

Non-Noether Conserved Quantity of Poincaré-Chetaev Equations of a Generalized Classical Mechanics

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Communications in Theoretical Physics 2006年第6期45卷 961-964页

作者： zhang peng-Yu fang jian-hui wang peng ding ning College of Physics Science and Technology China University of Petroleum （East China） Dongying 257061 China

In the present paper the Lie symmetrical non-Noether conserved quantity of the Poincaré Chetaev equations of a generalized classical mechanics under the general infinitesimal transformations of Lie groups is discussed. First, we establish the determining equations of Lie symmetry of the equations. Second, the Lie symmetrical non-Noether conserved quantity of the equations is deduced. Finally, an example is given to illustrate the application of the results.

关键词： Poincaré-Chetaev equations generalized classical mechanics Lie symmetry non-Noether conserved quantity

Noether-Mei Symmetry of Mechanical System in Phase Space

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Communications in Theoretical Physics 2006年第5期45卷 882-884页

作者： fang jian-hui wang peng ding ning College of Physical Science and Technology China University of Petroleum Dongying 257061 China

In this paper, a new kind of symmetry and its conserved quantities of a mechanical system in phase space are studied. The definition of this new symmetry, i,e., a Noether-Mei symmetry, is presented, and the criterion of this symmetry is also given. The Noether conserved quantity and the Mei conserved quantity deduced from the Noether-Mei symmetry of the system are obtained. Finally, two examples are given to illustrate the Bpplication of the results.

关键词： Noether-Mei symmetry conserved quantity mechanical system phase space

Two New Types of Conserved Quantities of Mei Symmetry for Holonomic Mechanical System

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Communications in Theoretical Physics 2008年第1期49卷 53-56页

作者： fang jian-hui wang peng ding ning College of Physics Science and Technology China University of Petroleum Dongying 257061 China

Two new types of conserved quantities directly deduced by Mei symmetry of holonomic mechanical system are studied. The definition and criterion of Mei symmetry for holonomic system are given. A coordination function is introduced, the conditions under which the Mei symmetry can directly lead to the two types of conserved quantities and the forms of the two types of conserved quantities are obtained. An illustrative example is given. The result indicates that the coordination function can be selected properly according to the demand of the gauge function, thereby the gauge function can be found out more easily. Furthermore, since the choice of the coordination function has multiformity, much T more conserved quantity of Mei symmetry for holonomic mechanical system can be obtained.

关键词： holonomic mechanical system Mei symmetry new conserved quantity

Perturbation and Adiabatic Invariants of Mei Symmetry for Nonholonomic Mechanical Systems

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Communications in Theoretical Physics 2007年第4期47卷 594-596页

作者： ding ning fang jian-hui wang peng College of Physical Science and Technology China University of Petroleum Dongying 257061 China

Based on the concept of adiabatic invariant, the perturbation and adiabatic invariants of the Mei symmetry for nonholonomic mechanical systems are studied. The exact invariants of the Mei symmetry for the system without perturbation are given. The perturbation to the Mei symmetry is discussed and the adiabatic invariants of the Mei symmetry for the perturbed system are obtained.

关键词： Mei symmetry perturbation adiabatic invariant nonholonomic mechanical system