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Recent beijing Spectroscopy (BES) results

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Science china(physics,Mechanics & Astronomy) 2008年第6期51卷 567-576页

作者： LI WeiGuo institute of high energy physics, {4. academy of Sciences, beijing 10004., china institute of high energy physics Chinese Academy of Sciences Beijing China

Recent experimental results from beijing Spectroscopy (BES) are reviewed, including the hadron spectroscopy from J/ψ decays, and a number of new states are found or confirmed, including σ, κ, X(1835), ωφ threshold enhancement in J/ψ→γωφ, a broad resonance in J/ψ→K + K ? π 0, decay studies of ψ(2S) and χ CJ , as well as the results of ψ(3770) non-D $ \bar D $ decays. The current status of BEPCII/BESIII, the major upgrade of BEPC/BESII, is also reported.

关键词： beijing Spectroscopy hadron spectroscopy charm physics BEPCII

Effects of cosmological constant on motion of UHECR particles

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Science china(physics,Mechanics & Astronomy) 2005年第1期48卷 44-56页

作者： CHEN Shaoxia & CHANG Zhe institute of high energy physics, {4. academy of Sciences, beijing 100039, china Graduate School of {4. academy of Sciences, beijing 100039, china institute of high energy physics Chinese Academy of Sciences Beijing 100039 China Graduate School Chinese Academy of Sciences Beijing 100039 China

Recent astronomical observations manifest that about two-thirds of the whole energy in the Universe is contributed by a small positive cosmological constant A (> 0). Then, an asymptotically de Sitter spacetime is premised naturally. However, physics in the de Sitter spacetime is very different from that in the Minkowski spacetime. As the first step, a covariant formalism of the kinematics in the de Sitter spacetime is presented here. By solving exactly the equations of motion for a field, we obtain the dispersion relation of a free particle. It is noticed that the dispersion relation is dependent on the degree of freedom of angular momentum of the particle. We show the threshold anomaly of the ultra high energy cosmic ray disappears naturally in the framework of the de Sitter kinematics.

关键词： ultrahigh energy cosmic ray, cosmological constant, curved spacetime.

Strong decays of N~*(1535) in an extended chiral quark model

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Science china(physics,Mechanics & Astronomy) 2009年第10期52卷 1452-1457页

作者： AN ChunSheng1,2,3 & ZOU BingSong1,2,3 1 institute of high energy physics,{4. academy of Sciences,beijing 10004.,china 2 Theoretical physics Center for Science Facilities,{4. academy of Sciences,beijing 10004.,china 3 Graduate University of {4. academy of Sciences,beijing 10004.,china institute of high energy physics Chinese Academy of Sciences Beijing China Theoretical physics Center for Science Facilities Chinese Academy of Sciences Beijing China Graduate University of chinese academy of Sciences Beijing China

The strong decays of the N*(1535) resonance are investigated in an extended chiral quark model by including the low-lying $ qqqq\bar q $ components in addition to the qqq component. The results show that these five-quark components in N*(1535) contribute significantly to the N*(1535) → Nπ and N*(1535) → Nη decays. The contributions to the Nη decay come from both the lowest energy and the next-tolowest energy five-quarks components, while the contributions to the Nπ decay come from only the latter one. Taking these contributions into account, the description for the strong decays of N*(1535) is improved, especially for the puzzling large ratio of the decays to Nη and Nπ.

关键词： N*(1535) strong decays five-quark components

The principle of relativity, kinematics and algebraic relations

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Science china(physics,Mechanics & Astronomy) 2010年第4期53卷 591-597页

作者： GUO HanYing1, HUANG ChaoGuang2,3, WU HongTu4.& ZHOU Bin5 1institute of Theoretical physics, chinese academy of Sciences, {4. 100190, china 2institute of high energy physics, chinese academy of Sciences, beijing 10004., china 3Theoretical physics Center for Science Facilities, chinese academy of Sciences, beijing 10004., china 4.epartment of Mathematics, Capital Normal University, beijing 10004., china 5Department of physics, {4. Normal University, {4. 100875, china institute of Theoretical physics Chinese Academy of Sciences Beijing China institute of high energy physics Chinese Academy of Sciences Beijing China Theoretical physics Center for Science Facilities Chinese Academy of Sciences Beijing China Department of Mathematics Capital Normal University Beijing China Department of physics Beijing Normal University Beijing China

Based on the relativistic principle and the postulate of universal invariant constants (c, l), all kinematic symmetries can be set up as the subsets of the Umov-Weyl-Fock-Hua transformations for the inertial motions. ... 详细信息

关键词： principle of relativity with (c l) Umov-Weyl-Fock-Hua transformations kinematics special relativity triple

Geochemical characteristics of rare earth elements in Wuhan section of the Yangtze River

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Journal of Environmental Sciences 1995年第1期7卷 44-51页

作者： Wang Lijun Zhang Shen Zhang Chaosheng(institute of Geography,chinese academy of Sciences,beijing 100101,{4.)Li Xiuxia(institute of high energy physics,chinese academy of Sciences,beijing 100080,{4.) Inst of Geog Chinese Academy of Sciences Beijing China China

ＧｅｏｃｈｅｍｉｃａｌｃｈａｒａｃｔｅｒｉｓｔｉｃｓｏｆｒａｒｅｅａｒｔｈｅｌｅｍｅｎｔｓｉｎＷｕｈａｎｓｅｃｔｉｏｎｏｆｔｈｅＹａｎｇｔｚｅＲｉｖｅｒＷａｎｇＬｉｊｕｎ；ＺｈａｎｇＳｈｅｎ；ＺｈａｎｇＣｈａｏｓｈｅ... 详细信息

ＧｅｏｃｈｅｍｉｃａｌｃｈａｒａｃｔｅｒｉｓｔｉｃｓｏｆｒａｒｅｅａｒｔｈｅｌｅｍｅｎｔｓｉｎＷｕｈａｎｓｅｃｔｉｏｎｏｆｔｈｅＹａｎｇｔｚｅＲｉｖｅｒＷａｎｇＬｉｊｕｎ；ＺｈａｎｇＳｈｅｎ；ＺｈａｎｇＣｈａｏｓｈｅｎｇ（ＩｎｓｔｉｔｕｔｅｏｆＧｅｏ...

关键词： geochemical characteristics rare earth elements Yangtze River

Narrow line Seyfert 1 galaxies: where are the broad line regions?

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Science china(physics,Mechanics & Astronomy) 2010年第12期53卷 2307-2311,2339-2343页

作者： MAO WeiMing 1,2,3 , HU Chen 2 , WANG JianMin 2 , BIAN WeiHao 4., ZHANG Shu 2 & ZHAO Gang 1 1 Key Laboratory of Optical Astronomy, National Astronomical Observatories, chinese academy of Sciences, beijing 100012, china 2 Key Laboratory for Particle Astro{4., institute of high energy {4., chinese academy of Sciences, beijing 10004., china 3 Graduate University of the chinese academy of Sciences, beijing 10004., china 4.Department of {4., Nanjing Normal University, Nanjing 210011, china Key Laboratory of Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences Beijing China Key Laboratory for Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing China Graduate University of the chinese academy of Sciences Beijing China Department of physics Nanjing Normal University Nanjing China

A sample consisting of 211 narrow line Seyfert 1 galaxies (NLS1s) with high quality spectra from the Sloan Digital Sky Survey (SDSS) is selected to explore where broad line regions are in these objects. We find that the Hβ profile can be fitted well by three (narrow, intermediate and broad) Gaussian components, and the FWHM ratios of the broad to the intermediate components hold a constant of 3.0 roughly for the entire sample. If the broad components originate from the region scaled by the well-determined Hβ reverberation mapping relation, we find that the intermediate components originate from the inner edge of the torus, which is scaled by dust K-band reverberation. We find that the IC and the BC are strongly linked dynamically, but the relation of their covering factors is much more relaxed, implying that both regions are clumpy.

关键词： black hole physics galaxies: evolution quasars: general

Patterns of platinum-group elements in mantle peridotite, granulite xenoliths and basalt in Hannuoba

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chinese Science Bulletin 1999年第18期44卷 1676-1681页

作者： CHU Xuelei, LI Xiaolin, XU Jiuhua and LIU Jianming1. The Research Center of Mineral Resources Exploration , chinese academy of Sciences , beijing 100101, china 2. {4. of Geology , chinese academy of Sciences , beijing 100029, china 3. {4. of high energy physics , chinese academy of Sciences , beijing 100817 , china 4. beijing University of Science and Engineering , beijing 100083, china Corresponding author The Research Center of Mineral Resources Exploration Chinese Academy of Sciences Beijing China institute of Geology Chinese Academy of Sciences Beijing China institute of high energy physics Chinese Academy of Sciences Beijing China beijing University of Science and Engineering Beijing China

Neutron activation analysis after preconcentration of nickel sulfide fire assay was used in measurement of Ru, Ph, Pd, Os, Ir, Pt (i.e. PGE elements) and Au concentrations for basalt, mantle and granulite xenoliths in Hannuoba. The chondrite- and primitive mantle-normalized PGE patterns generally exhibit flat (for Iherzolite), negative slope (for harzburgite),

关键词： mantle xenolith granulite xenolith basalt platinum-group element Hannuoba.

Compression behavior of Zr_(4.)Ti_(14.Cu_(12.5)Ni_(10)Be_(22.5) bulk metallic glass up to 24.GPa

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Science china(physics,Mechanics & Astronomy) 2005年第3期48卷 319-324页

作者： LI Gong 1, 2 , ZHAN Zaiji 2 , LIU Jing 3 , YUN Jinku 1 , SUN Liling 2 , LIU Riping 1 , ZHANG Jun 2 & WANG Wenkui 1, 2 1. Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004. china 2. Center for Condensed Matter physics, institute of physics, {4. academy of Sciences, beijing 100080, china 3. BSRF, institute of high energy physics, {4. academy of Sciences, beijing 100039, china Key Laboratory of Metastable Materials Science and Technology Yanshan University Qinhuangdao China Center for Condensed Matter physics Institute of Physics Chinese Academy of Sciences Beijing China BSRF Institute of High Energy Physics Chinese Academy of Sciences Beijing China

The compression of a Zr4.Ti14.u12.5Ni10Be22.5 bulk metallic glass (BMG) is investigated at room temperature up to 24.GPa using in-situ high pressure energy dispersive X-ray diffraction with a synchrotron radiation source. The pressure-induced structural relaxation is exhibited. It is found that below about 8 GPa, the existence of excess free volume contributes to the rapid structural relaxation, which gives rise to the rapid volumetric change, and the structural relaxation results in the structural stiffness under higher pressure.

关键词： bulk metallic glass, high pressure, structural relaxation, synchrotron radiation.

The establishment of crystal position look-up table for positron emission tomography with block detectors

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Science china(Technological Sciences) 2009年第8期52卷 2418-2423页

作者： CHAI Pei1,2 & SHAN BaoCi1 1 Key Laboratory of Nuclear Analytical Techniques, institute of high energy physics, {4. academy of Sciences, beijing 10004., china 2 Graduate University of {4. academy of Sciences, beijing 10004., china Key Laboratory of Nuclear Analytical Techniques Institute of High Energy Physics Chinese Academy of Sciences Beijing China Graduate University of chinese academy of Sciences Beijing China

A method has been developed to establish the crystal position look-up table for positron emission tomography with block detectors. It is based on the principle that the counts in crystal position histogram obey the Gaussian mixture model (GMM). This method has taken full consideration of the characteristics of the GMM and the detector itself. The experimental results have proved that it is simple, reliable, and universal.

关键词： positron emission tomography position look-up table 2-D position histogram