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Recent progress of cern RD50 Collaboration

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中国有色金属学会会刊：英文版 2006年第B1期16卷 133-136页

作者： P.LUUKKA Helsinki Institute of Physics CERN /EPCH-1211 GenevaSwitzerland

The objective of the cern RD50 Collaboration is to develop radiation hard semiconductor detectors for very high luminosity colliders, in particular, for the upgrade of the large hadron collider (LHC) which itself is scheduled to be operational in 2007. The approach of the RD50 has two major research lines, material engineering and device engineering. These are further subdivided into projects covering defect characterization and engineering, new detector materials, detector characterization, new detector structures and full detector systems. Presently, 264 members from 53 institutes are actively participating in the RD50 Collaboration. Detectors made of defect engineered substrates, e.g. high resistivity magnetic Czochralski (MCz-Si), epitaxial silicon (Epi-Si) on Czochralski silicon (Cz-Si) substrate, intentionally thermal donor (TD) compensated p-type MCz-Si and oxygen enriched (DOFZ) silicon, have been demonstrated by the RD50 Collaboration. An overview and highlights of the results of these defect engineering techniques were given in this report.

关键词：欧洲原子能研究机构 RD50协作组辐射硬度半导体探测器成员单位研究进展直拉硅衬底

Characteristics of δ^(18)O in precipitation over Eastern Monsoon China and the water vapor sources

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Chinese Science Bulletin 2010年第22期55卷 200-211页

作者： LIU JianRong SONG XianFang YUAN GuoFu SUN XiaoMin LIU Xin Key Laboratory of water Cycle & Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research ChineseAcademy of Sciences Beijing 100101 China Graduate University of Chinese Academy of Sciences Beijing 100049 China cern sub-center of water Beifing 100101 China

Monsoon circulation is an important carrier of water vapor transport, and it impacts the precipitation of the monsoonal regions through the constraints and controls of large-scale water vapor transport and distributions as well as the water vapor balance. An overall research on stable Hydrogen and Oxygen isotopes in precipitation over Eastern Monsoon China could benefit a comprehensive understanding of the monsoonal precipitation mechanism. Seventeen field stations of the Chinese Network of Isotopes in Precipitation (CHNIP) have been selected to collect monthly composite precipitation samples during the years 2005―2006. Components of δ D and δ 18O have been analyzed to achieve the spatiotemporal distributions. The established Local Meteoric water Line δ D=7.46δ 18O+0.90 based on the 274 obtained monthly samples could be treated as isotope input functions across the region, due to basically reflecting the specific regional meteorological conditions over Eastern Monsoon China. The δ-value depleted from coastal to inner area. In Southern China and Northeastern China there were typical periodic patterns of δ18O. Different dominant affecting metrological factors have been raised with different regions. From south to north, the temperature effect of δ18O enhanced, while the amount effect changed from existing at an all-year-scale in Southern China to being only remarkable during the main rainy seasons in North China and Northeastern China. Main geographical controls varied from altitude in Southern China and North China to latitude in Northeastern China. Furthermore, δ18O had an implication of advance and retreat of the monsoon as well as rainfall belt transfer. δ 18O was also a tracer for the movement path of typhoon and tropical storms.

关键词：中国东部季风环流降水机制水汽来源特征氧同位素水汽输送平衡控制

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Stable isotopes of summer monsoonal precipitation in southern China and the moisture sources evidence from δ^18O signature

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Journal of Geographical Sciences 2008年第2期18卷 155-165页

作者： LIU Jianrong SONG Xianfang YUAN Guofu SUN Xiaomin LIU Xin WANG Zhimin WANG Shiqin Key Laboratory of water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China Graduate University of Chinese Academy of Sciences Beijing 100039 China cern sub-center of water Beijing 100101 China

Summer monsoons （South Asian monsoon, South China Sea monsoon and subtropical monsoon） are prominent features of summertime climate over southern China. Dif- ferent monsoons carry different inflow moisture into China and control the temporal and spatial distributions of precipitation. Analyses of meteorological data, particularly wind, tempera- ture and pressure anomalies are traditional methods of characterizing moisture sources and transport patterns. Here, we try to utilize the evidence from stable isotopes signatures to trace summer monsoons over southern China. Based on seven CHNIP （Chinese Network of Iso- topes in Precipitation） observatory stations located in southern China, monthly composite precipitation samples have been collected and analyzed for the composition of δ^18O during July, 2005. The results indicated that the spatial distributions of δ^18O in precipitation could properly portray the moisture sources together with their transport pathways. Moreover, the amount effect, altitude effect, temperature effect and the correlation between δ^18O vs. relative humidity were discussed.

关键词： summer monsoon precipitation δ^18O vapor inflow corridors southern China

Isotopic composition of precipitation over Arid Northwestern China and its implications for the water vapor origin

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Journal of Geographical Sciences 2009年第2期19卷 164-174页

作者：柳鉴容宋献方孙晓敏袁国富刘鑫王仕琴 Key Laboratory of water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China Graduate University of Chinese Academy of Sciences Beijing 100039China cern sub-center of water Beijing 100101China

In order to reveal the characteristics and climatic controls on the stable isotopic composition of precipitation over Arid Northwestern China, eight stations have been selected from Chinese Network of Isotopes in Precipitation(CHNIP).During the year 2005 and 2006, monthly precipitation samples have been collected and analyzed for the composition of δD and δ*** established local meteoric water line δD=7.42δ18O+1.38, based on the 95 obtained monthly composite samples, could be treated as isotopic input function across the *** deviations of slope and intercept from the Global Meteoric water Line indicated the specific regional meteorological *** monthly δ18O values were characterized by a positive correlation with surface air temperature(δ18O(‰) =0.33 T(℃)-13.12).The amount effect visualized during summer period(δ18O(‰) =-0.04P(mm)-3.44) though not appeared at a whole *** distributions of δ18O have properly portrayed the atmospheric circulation background in each month over Arid Northwestern *** quan-titative simulation of δ18O, which involved a Rayleigh fractionation and a kinetic fractionation, demonstrated that the latter one was the dominating function of condensation of ***, the raindrop suffered a re-evaporation during falling processes, and the precipitation vapor might have been mixed with a quantity of local recycled water *** linear regression equations and a δ18O-T relation have been gained by using meteorological parameters and δ18O data to evaluate physical controls on the long-term *** established δ18O-T relation, which has been based on the present-day precipitation, could be considered as a first step of quantitatively reconstructing the historical environmental climate.

关键词： Arid Northwestern China (ANC) δ^18O precipitation water vapor origin

Highlights from the COMPASS experiment

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Chinese Physics C 2010年第9期34卷 1269-1274页

作者： G.K.Mallot cern PH Department(Switzerland)

The Compass experiment at cern is studying the nucleon spin structure with a 160 GeV polarized muon beam and polarized targets as well as hadron structure with 190 GeV pion,kaon and proton *** paper gives an overview of the results for the helicity and transverse spin structure of the nucleon.A first result from the spectroscopy experiments,the observation of a resonance with exotic J P C = 1-＋ quantum numbers at 1660 MeV is also *** paper ends with an outlook to future measurements.

关键词： nucleon structure spin deep inelastic scattering hadron spectroscopy exotic mesons

A pedagogical review on solvable irrelevant deformations of 2D quantum field theory

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Communications in Theoretical Physics 2021年第5期73卷 118-156页

作者： Yunfeng Jiang cern Theory Department GenevaSwitzerland

This is a pedagogical review on TT^(-)deformation of two dimensional quantum field *** is based on three lectures which the author gave at ITP-CAS in December *** review consists of four *** first part is a general introduction to TT^(-)*** emphasises are put on the deformed classical Lagrangian and the exact solvability of the *** second part focuses on the torus partition sum of the TT^(-)/JT^(-)deformed conformal field theories and modular invariance/*** the third part,different perspectives of TT^(-)deformation are presented,including its relation to random geometry,2D topological gravity and *** summarize more recent developments until January 2021 in the last part.

关键词： irrelevant deformation integrability conformal field theory 2D gravity holographic duality

News on the physics potential of the reaction e^+e^-→ Zγ

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Science China(Physics,Mechanics & Astronomy) 2021年第2期64卷 27-28页

作者： Philipp Roloff cern CH-1211Geneva 23Switzerland

The next large project in particle physics is widely expected to be a high-energy electron-positron *** a facility could be realised as a circular collider,like the Circular Electron Positron Collider(CEPC)and the Future e^+e^-Circular Collider(FCC-ee)[1],or as a linear collider,like the International Linear Collider(ILC)and the Compact Linear Collider(CLIC)[2].

关键词： circular positron potential

RADIOACTIVITY AND RADIATION PROTECTION

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Chinese Physics C 2016年第10期40卷 510-515页

作者： S. Roesler M. Silari cern

36.1. Definitions [1,2] It would be desirable if legal protection limits could be expressed in directly measurable physical quantities. However, this does not allow to quantify biological effects of the exposure of the human body to ionizing radiation. For this reason, protection limits are expressed in terms of so-called protection quantities which, although calculable, are not measurable. Protection quantities quantify the extent of exposure of the human body to ionizing radiation from both whole and partial body external irradiation and from intakes of radionucUdes.

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Simulating CO_2 flux of three different ecosystems in ChinaFLUX based on artificial neural networks

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Science China Earth Sciences 2006年第S2期49卷 252-261页

作者： HE Honglin, YU Guirui, ZHANG Leiming, SUN Xiaomin & SU Wen Key Laboratory of Ecosystem Network Observation and Modeling, cern Synthesis Research center, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China Key Laboratory of Ecosystem Network Observation and Modeling CERN Synthesis Research Center Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China

The nonlinearity of the relationship between CO2 flux and other micrometeorological variables flux parameters limits the applicability of carbon flux models to accurately estimate the flux dynamics. However, the need for carbon dioxide (CO2) estimations covering larger areas and the limitations of the point eddy covariance technique to address this requirement necessitates the modeling of CO2 flux from other micrometeorological variables. Artificial neural networks (ANN) are used because of their power to fit highly nonlinear relations between input and output variables without explaining the nature of the phenomena. This paper applied a multilayer perception ANN technique with error back propagation algorithm to simulate CO2 flux on three different ecosystems (forest, grassland and cropland) in ChinaFLUX. Energy flux (net radiation, latent heat, sensible heat and soil heat flux) and temperature (air and soil) and soil moisture were used to train the ANN and predict the CO2 flux. Diurnal half-hourly fluxes data of observations from June to August in 2003 were divided into training, validating and testing. Results of the CO2 flux simulation show that the technique can successfully predict the observed values with R2 value between 0.75 and 0.866. It is also found that the soil moisture could not improve the simulative accuracy without water stress. The analysis of the contribution of input variables in ANN shows that the ANN is not a black box model, it can tell us about the controlling parameters of NEE in different ecosystems and micrometeorological environment. The results indicate the ANN is not only a reliable, efficient technique to estimate regional or global CO2 flux from point measurements and understand the spatiotemporal budget of the CO2 fluxes, but also can identify the relations between the CO2 flux and micrometeorological variables.

关键词： artificial neural network CO2 ChinaFLUX energy flux variables contribution.