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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 energy physics,Chinese academy of sciences,{3.,china institute of high energy physics Chinese Academy of Sciences Beijing China

physics opportunity in the charm and τ energy region calls for higher luminosity of the {3. 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 high 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

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 institute of high energy physics,Chinese academy of sciences,{3.,china 2 Theoretical physics center for Science Facilities,Chinese academy of sciences,{3.,china 3.Graduate University of Chinese academy of sciences,{3.,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*(153.) resonance are investigated in an extended chiral quark model by including the low-lying qqqqq components in addition to the qqq *** results show that these five-quark components in N*(153.) contribute significantly to the N*(153.)→ Nπ and N*(153.) → Nη *** contributions to the Nη decay come from both the lowest energy and the next-to-lowest energy five-quarks components,while the contributions to the Nπ decay come from only the latter *** 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

Formalism of Helicity Coupling Amplitudes for J/Ψ→π+π~-π0*

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Communications in Theoretical physics 2007年第1期47卷 89-94页

作者： PING Rong-Gang LI Gang WANG Zheng institute of high energy physics,the Chinese academy of sciences,{3.,china china center for Advance Science and Technology (CCAST),beijing 100080,china institute of high energy physics the Chinese Academy of Sciences Beijing 100049 China china center for Advance Science and Technology (CCAST) Beijing 100080 China

The formalisms of helicity coupling amplitudes for J/ψ→π~+π~-π~0 are presented.A detailed discussionis also given on the barrier factor,Breit-Wigner,and density matrix.A Monte Carlo simulation of J/ψ→p(770)π→π~+π~-π~0 is carried *** results show that the p(770) resonance is well reproduced compared with experimental data.

关键词： helicity coupling amplitude J/ψ decays ρπ puzzle

Observation constraints of the hard X-ray modulation telescope HXMT

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Science china(physics,Mechanics & Astronomy) 2010年第S1期53卷 31-35页

作者： LU Yu1,2,ZHANG WenZhao3.QU JinLu1,SONG LiMing1,GAO Jian3.ZHANG HongMei4 & OU Ge4 1 Key Laboratory of Particle Astrophysics,institute of high energy physics,Chinese academy of {3.,beijing 100049,china 2 Graduate University of Chinese academy of {3.,beijing 100049,china 3.Department of Astronomy,beijing Normal University,beijing 100875,china {13.,institute of high energy physics,Chinese academy of {3.,beijing 100049,china Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing China Graduate University of Chinese academy of sciences Beijing China Department of Astronomy Beijing Normal University Beijing China computing center Institute of High Energy Physics Chinese Academy of Sciences Beijing China

The hard X-ray modulation telescope HXMT is a low orbit X-ray space telescope whose main science goals are to accomplish a hard X-ray all sky survey and to study timing and spectral characteristics of X-ray *** has three kinds of science instruments:the high energy X-ray detector(HE),the medium energy X-ray detector(ME) and the low energy X-ray detector(LE).The observation schedule of HXMT is a key to achieving the science goal of HXMT,and the analysis of the observation constraints is one of the first tasks in making the observation *** paper analyzes how the observation constraints influence the sky visibility and the visible time distribution of X-ray sources and discusses the schedule strategy with regard to the observation constraints.

关键词： HXMT observation constraints sky visibility

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 {3., beijing 100190, china 2institute of high energy physics, Chinese academy of {3., beijing 100049, china 3.heoretical physics center for Science Facilities, Chinese academy of {3., beijing 100049, china 4Department of Mathematics, Capital Normal University, beijing 100048, china 5Department of physics, beijing Normal University, beijing 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

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 physics,Chinese academy of sciences,{3.,china 2 Graduate University of Chinese academy of sciences,{3.,china 3.Key Lab of Nuclear Detection Technology and Nuclear Electronics of Chinese academy of sciences,{3.,china institute of high energy physics Chinese Academy of Sciences Beijing China Graduate University of Chinese academy of sciences Beijing China Key Lab of Nuclear Detection Technology and Nuclear Electronics of Chinese academy of sciences Beijing 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 china 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

Systematic distortion in cosmic microwave background maps

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Science china(physics,Mechanics & Astronomy) 2009年第5期52卷 804-808页

作者： LIU Hao 1,3.&LI TiPei 1,2 1Key Laboratory of Particle Astrophysics,institute of high energy physics,Chinese academy of {3.,beijing 100049,china 2center for Astrophysics,Tsinghua University,beijing 100084,china 3.Graduate University of Chinese academy of {3.,beijing 100049,china Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing China Graduate University of Chinese academy of sciences Beijing China center for Astrophysics Tsinghua University Beijing China

To minimize instrumentally the induced systematic errors,cosmic microwave background(CMB)anisotropy experiments measure temperature differences across the sky using pairs of horn antennas, temperature map is recovered from temperature difference obtained in sky survey through a map-making *** inspect and calibrate residual systematic errors in the recovered temperature maps is important as most previous studies of cosmology are based on these *** analyzing pixel-ring coupling and latitude dependence of CMB temperatures,we find notable systematic devia- tion from CMB Gaussianity in released Wilkinson Microwave Anisotropy Probe(WMAP)*** detected deviation cannot be explained by the best-fit LCDM cosmological model at a confidence level above 99%and cannot be ignored for a precision cosmology study.

关键词： cosmology cosmic microwave background methods data analysis

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, {3. 2 Key Laboratory for Particle Astrophysics, institute of high energy physics, Chinese academy of sciences, beijing 100049, {3. 3.Graduate University of the Chinese academy of sciences, beijing 100049, {3. 4 Department of physics, Nanjing Normal University, Nanjing 210011, {3. 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

Compression behavior of Zr_(41)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, {3. of physics, Chinese academy of sciences, beijing 100080, china 3. BSRF, institute of high energy physics, Chinese academy of sciences, beijing 10003., 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 Zr41Ti14Cu12.5Ni10Be22.5 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.