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Studies on BEPC upgrade from pretzel to double-ring

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Science china(physics,Mechanics & Astronomy) 2010年第11期53卷 2084-2089页

作者： ZHANG Chuang institute of high {2. {3.,chinese academy of sciences,Beijing 100049,china 1. institute of high {2. {3. Chinese Academy of Sciences Beijing 100049 China

physics opportunity in the charm and τ energy region calls for {2.er luminosity of the Beijing Electron-Positron Collider (BEPC).The BEPC has experienced continuous improvement since its completion in ***,as a major upgrading project of the BEPC,aims at enhancing its luminosity of factor 3.–100,following the principle of "one machine,two purposes" as adopted in BEPC,so that both {2. energy physics and synchrotron radiation experiments can be carried out with *** the BEPC to BEPCII,the double-ring scheme with multi-bunch e +-e-collision in the large crossing angle was studied in comparison with the single-ring pretzel *** the dedicated synchrotron radiation operation,artful "bridges" are designed to connect two halves of the outer ring in both the southern and the northern crossing *** paper reviews the studies on the BEPC upgrade from pretzel to double-ring structure of BEPCII.

关键词： collider storage ring high energy physics synchrotron radiation

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 {2. {3., chinese academy of sciences, Beijing 100049, china 1. institute of high {2. {3. Chinese Academy of Sciences Beijing 100049 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(183.), ωφ threshold enhancement in J/ψ→γωφ, a broad resonance in J/ψ→K + K ? π 0, decay studies of ψ(2.) and χ CJ , as well as the results of ψ(3.70) 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

Strong decays of N~*(153.) 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 {2. of high energy {3.,chinese academy of sciences,Beijing 100049,china 2.Theoretical {3. Center for Science Facilities,chinese academy of sciences,Beijing 100049,china 3.Graduate University of chinese academy of sciences,Beijing 100049,china institute of high {2. {3. Chinese Academy of Sciences Beijing 100049 China Theoretical physics Center for Science Facilities Chinese Academy of Sciences Beijing 100049 China Graduate University of chinese academy of {2. Beijing 100049 China

The strong decays of the N*(153.) 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*(153.) contribute significantly to the N*(153.) → Nπ and N*(153.) → 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*(153.) is improved, especially for the puzzling large ratio of the decays to Nη and Nπ.

关键词： N*(153.) strong decays five-quark components

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. {2. of Geology , chinese academy of sciences , Beijing 10002., china 3. institute 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 {2. {3. 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.

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 {2. {3., chinese academy of sciences, Beijing 10003., china Graduate School of chinese academy of sciences, Beijing 10003., china institute of high {2. {3. 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 {2. energy cosmic ray disappears naturally in the framework of the de Sitter kinematics.

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

A 12.bit multichannel ADC for pixel detectors in particle physics and nuclear imaging

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Science china(Technological sciences) 2010年第5期53卷 1208-1214页

作者： WEI Wei1,2.3.WANG Zheng1,3.& ZHAO JingWei1,3.1 institute of high energy {3.,chinese academy of sciences,Beijing 100049,china 2.Graduate University of chinese academy of sciences,Beijing 100049,china 3.Key Lab of Nuclear Detection Technology and Nuclear Electronics of chinese academy of sciences,Beijing 100049,china 1. institute of high {2. {3. Chinese Academy of Sciences Beijing 100049 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. Key Lab of Nuclear Detection Technology and Nuclear Electronics of Chinese Academy of Sciences Beijing 100049 China

Modern pixel detectors in nuclear and particle physics experiments and also in nuclear imaging,starve for highly integrated application specified integrated circuit(ASIC),whereas in{2. the study of ASIC still stays far away from practical *** lack of ASIC strictly limits the research and development of domestic high energy physics field.A 12.bit multichannel ADC designed for high density readout is introduced as a major candidate for solution.A precise model is discussed and the simulation fully agrees with the model,which indicates a key principle of *** is performed according to the given rule,and novel layout techniques are carried *** results in all aspects are also obtained,showing an excellent real performance,which satisfies the practical requirement.

关键词： application specified integrated circuit high density readout Wilkinson ADC multi-channel ADC

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 {2. of {3.,Beijing 100101,china)Li Xiuxia(institute of high energy physics,chinese {2. of {3.,Beijing 100080,china) Inst of Geog Chinese Academy of Sciences Beijing China China

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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 {2. of sciences, Beijing 100012.{3. 2.Key Laboratory for Particle Astrophysics, institute of high energy physics, chinese {2. of sciences, Beijing 100049,{3. 3.Graduate University of the chinese {2. of sciences, Beijing 100049,{3. 4 Department of physics, Nanjing Normal University, Nanjing 2.0011,{3. 1. Key Laboratory of Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China2. Key Laboratory for Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China3. Graduate University of the Chinese Academy of Sciences Beijing 100049 China4. Department of Physics Nanjing Normal University Nanjing 210011 China

A sample consisting of 2.1 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

Direct CP violation in hadronic B decays

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Science china(physics,Mechanics & Astronomy) 2006年第3期49卷 357-366页

作者： HONG Bihai1,2.& Lü Caidian3.1. Department of physics, Lishui University, Lishui 3.3.00,china 2. Department of physics, Shanghai Jiaotong University, Shanghai 2.003.,{3. 3. institute of high energy physics, Beijing 100049,china Department of physics Lishui University Lishui 323000 China Department of physics Shanghai Jiaotong University Shanghai 200030 China institute of high {2. {3. Beijing 100049 China

There are different approaches for the hadronic B decay calculations, recently. In this paper, we upgrade three of them, namely factorization, QCD factorization and the perturbative QCD approach based on kT factorization, using new parameters and full wave functions. Although they get similar results for many of the branching ratios, the direct CP asymmetries predicted by them are different, which can be tested by recent experimental measurements of B factories.

关键词： CP violation hadronic B decay factorization.