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Testing local realism in P → VV decays

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science china(physics,Mechanics & Astronomy) 2010年第5期53卷 870-875页

作者： LI JunLi1 & QIAO CongFeng1,2 1Department of physics,Graduate University of chinese academy of sciences,beijing 100049,china 2Theoretical physics center for science facilities(TPCSF),chinese academy of sciences,beijing 100049,china 1. Department of physics Graduate University of Chinese Academy of Sciences Beijing 100049 China2. Theoretical Physics Center for Science Facilities (TPCSF) Chinese Academy of Sciences Beijing 100049 China

It was found that the vector meson pair from the pseudoscalar decays can form an entangled *** this work we give out detailed explanations on the polarization correlation of the two entangled vector *** is demonstrated that an experimental test of the Clauser-Horne inequality can be carried out through measuring the azimuthal distribution of four pseudoscalars in the cascade decay ηc→ VV →(PP)(PP),and the measurement of this process is feasible with the current running experiments in tau-charm ***,a brief discussion on the polarization correlation of the two vector mesons from B → VV decays is also presented.

关键词： nonlocality test high energy experiment meson decays

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, beijing 100190, china 2Institute of High Energy physics, chinese academy of sciences, beijing 100049, china 3.heoretical physics center for science facilities, chinese academy of sciences, beijing 100049, china 4Department of Mathematics, Capital Normal University, beijing 100048, china 5Department of physics, beijing Normal University, beijing 100875, china 1. Institute of Theoretical physics Chinese Academy of Sciences Beijing 100190 China2. Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China3. Theoretical Physics Center for Science Facilities Chinese Academy of Sciences Beijing 100049 China4. Department of Mathematics Capital Normal University Beijing 100048 China5. Department of Physics Beijing Normal University Beijing 100875 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

The gravity wave instability induced by photochemistry in summer polar mesopause region

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chinese science Bulletin 2000年第3期45卷 267-272页

作者： center for Space science and Applied Research, chinese academy of sciences, beijing 100080, china Laboratory of Numeric Study of Heliospheric physics, chinese academy of sciences, beijing 100080, china center for Space science and Applied Research Chinese Academy of Sciences Beijing China Laboratory of Numeric Study of Heliospheric physics Chinese Academy of Sciences Beijing China

The effect of diabatic process due to the photochemical heating and cooling on the gravity wave propagation in middle atmosphere is studied. A linear gravity wave model which considers the diabatic process is established. The unstable region and the growth rate of the gravity wave caused by photochemistry are calculated. And the comparison between the model and the adiabatic gravity wave theory of pure dynamics is made. The results indicate that the photochemical heating process can induce the instability of gravity wave at mesopause. The intensity of the instability becomes stronger as the temperature decreases. The temperature feature and the altitude characteristics of the instability are consistent with the observation. Therefore, the instability of the gravity wave induced by photochemistry may be an important mechanism in polar mesopause region in summer.

关键词： photochemistry instability gravity wave growth rate.

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 sciences,beijing 100049,china 2center for Astrophysics,Tsinghua University,beijing 100084,china 3 Graduate University of chinese academy of sciences,beijing 100049,china Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China center for Astrophysics Tsinghua University Beijing 100084 China Graduate University of chinese academy of sciences Beijing 100049 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

Observation results of relativistic electrons detected by Fengyun-1 satellite and analysis of relativistic electron enhancement (REE) events

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science china(physics,Mechanics & Astronomy) 2008年第12期51卷 1947-1956页

作者： YANG XiaoChao1,2↑ & WANG ShiJin1 1 center for Space science and Applied Research, chinese academy of sciences, beijing 100190, china 2 Graduate University of chinese academy of sciences, beijing 100049, china 1. center for Space science and Applied Research Chinese Academy of Sciences Beijing 100190 China 2. Graduate University of chinese academy of sciences Beijing 100049 China

The space particle component detector on Fengyun-1 satellite which works at the sun-synchronous orbit of about 870 km altitude has detected relativistic electrons for a long time. In comparison with the SAMPEX satellite observations during 1999–2004, the relativistic electron data from Fengyun-1 satellite from June 1999 to 2005 are used to analyze the relativistic electron enhancement (REE) events at the low earth orbit, and the possible correlation among REE events at the low earth orbit, high-speed solar wind and geomagnetic storms is discussed. The statistical result presents that 45 REE events are found in total during this time period, and the strong REE events with the maximum daily average flux > 400 cm?2·srt-1·s?1 occur mostly during the transition period from solar maximum to solar minimum. Among these 45 REE events, four strong REE events last a longer time period from 26-to 51-day and correlate closely with high speed solar wind and strong geomagnetic storms. Meanwhile, several strong geomagnetic storms occur continuously before these REE events, and these continuous geomagnetic storms would be an important factor causing these long-lasting strong REE events. The correlation analysis for overall 45 events indicates that the strength of the REE events correlates with the solar wind speed and the strength of the geomagnetic storm, and the correlation for strong REE events is much stronger than that for weak REE events.

关键词： relativistic electron enhancement low earth orbit high-speed solar wind geomagnetic storm

Interannual variability of Antarctic Oscillation and its influence on East Asian climate during boreal winter and spring

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science china Earth sciences 2006年第5期49卷 554-560页

作者： FAN Ke1,2,3 & WANG Huijun2 1. Nansen-Zhu International Research center, Institute of Atmospheric physics, chinese academy of sciences, beijing 100029, china 2. Department of Atmospheric science, Yunnan University, Kunming 650091, china 3. Graduate University of the chinese academy of sciences, beijing 100049, china 1. Nansen-Zhu International Research center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 2. Department of Atmospheric science Yunnan University Kunming 650091 China 3. Graduate University of the chinese academy of sciences Beijing 100049 China

The interannual variability of Antarctic Oscillation (AAO) and its influence on East Asian climate during both boreal winter and spring are addressed. The results show that the positive AAO anomaly decreases the cold activity over East Asia during both boreal winter and spring. AAO-related barotropic meridional teleconnection from Antarctic to Arctic is found through analysis of mean me- ridional circulations. This meridional teleconnection is remarkable over Eurasia during boreal winter and over the Pacific Ocean during boreal spring. The results also show that zonal mean zonal wind at high latitudes in Southern Hemisphere has well positive correlation with that of Eurasia during boreal winter and has negative correlation with Pacific North American teleconnection (PNA) during boreal spring, which again display the meridional teleconnection. Thus, local meridional teleconnection is a possible linkage for interaction of circulations at mid-high latitudes between both hemispheres.

关键词： Antarctic Oscillation, Eurasian west wind, meridional teleconnection, mean meridional circulation.

Forecasting the summer rainfall in North china using the year-to-year increment approach

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science china Earth sciences 2009年第4期52卷 532-539页

作者： FAN Ke1, LIN MeiJing1,2 & GAO YuZhong3 1 Nansen-Zhu International Research center, Institute of Atmospheric physics, chinese academy of sciences, beijing 100029, china 2 Graduate University of the chinese academy of sciences, beijing 100049, china 3 Heilongjiang Meteorological Administration, Harbin 150030, china Nansen-Zhu International Research center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Graduate University of the chinese academy of sciences Beijing 100049 China Heilongjiang Meteorological Administ

A new approach to forecasting the year-to-year increment of rainfall in North china in July-August (JA) is proposed. DY is defined as the difference of a variable between the current year and the preceding year (year-to-year increment). NR denotes the seasonal mean precipitation rate over North china in JA. After analyzing the atmospheric circulation anomalies associated with the DY of NR, five key predictors for the DY of NR have been identified. The prediction model for the DY of NR is established by using multi-linear regression method and the NR is obtained (the current forecasted DY of NR added to the preceding observed NR). The prediction model shows a high correlation coefficient (0.8) between the simulated and the observed DY of NR throughout period 1965-1999, with an average relative root mean square error of 19% for the percentage of precipitation rate anomaly over North china. The prediction model makes a hindcast for 2000-2007, with an average relative root mean square error of 21% for the percentage of precipitation rate anomaly over North china. The model reproduces the downward trend of the percentage of precipitation rate anomaly over North china during 1965-2006. Because the current operational prediction models of the summer precipitation have average forecast scores of 60%-70%, it has been more difficult to forecast the summer rainfall over North china. Thus this new approach for predicting the year-to-year increment of the summer precipitation (and hence the summer precipitation itself) has the potential to significantly improve operational forecasting skill for summer precipitation.

关键词： annual increment North china precipitation prediction prediction skill

Some characteristics of the atmosphere during an adiabatic process

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Progress in Natural science:Materials International 2006年第6期16卷 644-648页

作者： GAO Li, LI Jianping and REN Hongli (LASG, Institute of Atmospheric physics, chinese academy of sciences, beijing 100029, china Graduate School of chinese academy of sciences, beijing 100049, china National Climate center, Laboratory of Climate Studies, china Meteorological Administration, beijing 100081, china) [a]LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China [b]Graduate School of chinese academy of sciences Beijing China [c]National Climate center Laboratory of Climatic Studies China Meterological Administration Beijing China

Some important characteristics of the atmosphere during an adiabatic process are investigated, which include the invariability of atmospheric entropy range and local surface potential temperature, the conservation of the atmospheric mass intervened between any isentropic surface and the ground, and the isentropic surface intersecting with the ground. The analysis shows that the atmospheric reference state (ARS) for investigation on available potential energy (APE) should be defined objectively as the state which could be approached from the existing atmosphere by adiabatic adjustment, and be related to initial atmospheric state before adjustment. For the initial atmosphere state at any time, its corresponding ARS is different from the one at another time. Based on the above-mentioned conclusions, the reference state proposed by Lorenz cannot be obtained physically, so a new conception, the conditional minimum total potential energy, is put forward in order to objectively investigate atmospheric APE.

关键词： available potential energy adiabatic isentropic surface atmospheric reference state conditional minimum total potential energy.

fMRI time series analysis based on stationary wavelet and spectrum analysis

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Progress in Natural science:Materials International 2006年第11期16卷 1171-1176页

作者： ZHI Lianhe~ 1,2,3 , ZHAO Xia~4, SHAN Baoci~1**, PENG Silong~5, YAN Qiang~1, YUAN Xiuli~1 and TANG Xiaowei~ 1,6 (1. Key Laboratory of Nuclear Analysis Techniques, Institute of High Energy physics, chinese academy of sciences, beijing 100049, china 2. Graduate School of chinese academy of sciences, beijing 100049, china 3. Department of physics, Zhoukou Normal University, Zhoukou 466100, china 4. Research Imaging center, University of Texas Health science center, San Antonio, Texas 78229, USA 5. National ASIC Design and Engineering center, Institute of Automation, chinese academy of sciences, beijing 100049, china 6. Department of physics, Zhejiang University, Hangzhou 310027, china) [a]Key Laboratory of Nuclear Analysis Techniques Institute of High Energy Physics Chinese Academy of Sciences Beijing China [b]Graduate School of chinese academy of sciences Beijing China [c]Department of physics Zhoukou Normal University Zhoukou China [d]Research Imaging center University of Texas Health Science Center San Antonio Texas USA [e]National ASIC Design and Engineering center Institute of Automation Chinese Academy of Sciences Beijing China [f]Department of physics Zhejiang University Hangzhou China

The low signal to noise ratio (SNR) of functional MRI (fMRI) prefers more sensitive data analysis methods. Based on stationary wavelet transform and spectrum analysis, a new method with high detective sensitivity was developed for analyzing fMRI time series, which does not require any prior assumption of the characteristics of noises. In the proposed method, every component of fMRI time series in the different time-frequency scales of stationary wavelet transform was discerned by the spectrum analysis, then the components from noises were removed using the stationary wavelet transform, finally the components of real brain activation were detected by cross-correlation analysis. The results obtained from both simulated and in vivo visual experiments illustrated that the proposed method has much higher sensitivity than the traditional cross-correlation method.

关键词： fMRI stationary wavelet transform spectrum analysis data analysis.