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Constraints on Cardassian universe from Gamma ray bursts

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Science china(physics,Mechanics & Astronomy) 2010年第9期53卷 1720-1725页

作者： wang taishan1 & liANG Nan2 1 {3. of physics & center for Astrophysics,tsinghua university,Beijing 100084,china 2 {3. of Astronomy,Beijing Normal university,Beijing 100875,china department of physics & center for Astrophysics Tsinghua University Beijing China department of Astronomy Beijing Normal University Beijing China

Constraints on the original Cardassian model and the modified polytropic Cardassian model are examined from the recently derived 42 gamma-ray bursts(GRBs) data calibrated with the method that can avoid the circularity *** results show that GRBs can be an optional observation to constrain the Cardassian *** the GRBs data with the newly de-rived size of baryonic acoustic oscillation peak from the Sloan Digital Sky Survey(SDSS),and the position of the first acoustic peak of the Cosmic Microwave Background radiation(CMB) from Wilkinson Microwave Anisotropy Probe(WMAP),we find Ωm0=0.27+0.02-0.02,n=0.06+0.07-0.08(1σ) for the original Cardassian model,and Ωm0=0.27+0.23.0.02,n=-0.09+0.23.1.91,β=0.82+2.10-0.62(1σ) for the modified polytropic Cardassian model.

关键词： Cardassian Gamma ray burst Cosmic Microwave Background baryonic acoustic oscillation

Inconsistency between WMAP data and released map

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Chinese Science Bulletin 2010年第10期55卷 907-909页

作者： liU Hao1 & li tipei1,2,3.1 Key Laboratory of Particle Astro{3.,Institute of High Energy {3.,Chinese Academy of Sciences,Beijing 100049,china 2 department of {3. & center for Astro{3.,tsinghua university,Beijing 100084,china 3.department of Engineering {3. & center for Astro{3.,tsinghua university,Beijing 100084,china Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing China department of physics & center for Astrophysics Tsinghua University Beijing China department of Engineering physics & center for Astrophysics Tsinghua University Beijing China

A remarkable inconsistency between the calibrated differential time-ordered data (TOD) of the Wilkinson Microwave Anisotropy Probe (WMAP) mission,which is the input for map-making,and the cosmic microwave background (CMB) temperature maps published by the WMAP team is revealed,indicating that there must exist a serious problem in the map making routine of the WMAP *** inconsistency is easy to be confirmed without the use of WMAP map-making *** view of the importance of this issue for cosmology study,we invite readers to check it by themselves.

关键词：威尔金森微波各向异性探测器 WMAP 地图制作宇宙微波背景有序数据制作软件 TOD CMB

Bifurcation timescales in power spectra of black hole binaries and ultraluminous X-ray sources

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Science china(physics,Mechanics & Astronomy) 2010年第S1期53卷 177-182页

作者： wang taishan1 & li tipei1,2 1 department of physics & {3. for Astrophysics,tsinghua university,Beijing 100084,china 2 Key Laboratory of Particle Astrophysics,Institute of High Energy physics,Chinese Academy of Sciences,Beijing 100049,china department of physics & center for Astrophysics Tsinghua University Beijing China Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing China

For black hole binaries(BHBs) and active galactic nuclei(AGNs),bifurcation timescales(BTs) Δtb exist,below which time-domain power is significantly higher than the corresponding Fourier ***-periodic oscillations(QPOs) are removed from the Fourier spectra of BHBs.A relationship between BT,black hole mass and bolometric luminosity is *** anti-correlation between BT and luminosity of Cyg X-1 is *** removing the QPOs,BTs are also obtained for two ultraluminous X-ray sources(ULXs),M82 X-1 and NGC5408 *** results support that they harbor intermediate mass black holes(IMBHs).

关键词： black hole binary ultraluminous X-ray source power spectral density data analysis

The relativistic consistent angular-momentum projected shell model study of the N=Z nucleus ^(52)Fe

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Science china(physics,Mechanics & Astronomy) 2009年第10期52卷 1471-1476页

作者： li YanSong1,2 & LONG GuiLu1,2 1 department of physics,{3.,Beijing 100084,china 2 center of Nuclear Theory,National Laboratory of Heavy Ion Accelerator of Lanzhou,Lanzhou 73.000,china department of physics Tsinghua University Beijing China center of Nuclear Theory National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou China

The relativistic consistent angular-momentum projected shell model(ReCAPS) is used in the study of the structure and electromagnetic transitions of the low-lying states in the N=Z nucleus *** model calculations show a reasonably good agreement with the *** backbending at 12+ is reproduced and the energy level structure suggests that neutron-proton interactions play important roles.

关键词： ReCAPS relativistic mean field angular-momentum projection method 52Fe neutron-proton interaction

The correlation timescale of the X-ray flux during the outbursts of soft X-ray transients

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Science china(physics,Mechanics & Astronomy) 2010年第S1期53卷 161-167页

作者： WU YuXiang1,2,YU WenFei1 & li tipei2 1 Shanghai Astronomical Observatory,Shanghai 100012,china 2 {3. of Engineering physics & center for Astrophysics,tsinghua university,Beijing 100084,china Shanghai Astronomical Observatory Shanghai China department of Engineering physics & center for Astrophysics Tsinghua University Beijing China

Recent studies of black hole and neutron star low mass X-ray binaries(LMXBs) show a positive correlation between the X-ray flux at which the low/hard(LH)-to-high/soft(HS) state transition occurs and the peak flux of the following HS *** analyzing the data from the All Sky Monitor(ASM) onboard the Rossi X-ray Timing Explorer(RXTE),we show that the HS state flux after the source reaches its HS flux peak still correlates with the transition flux during soft X-ray transient(SXT) *** studying large outbursts or flares of GX 3.9-4,Aql X-1 and 4U 1705-44,we have found that the correlation holds up to 250,40,and 50 d after the LH-to-HS state transition,*** time scales correspond to the viscous time scale in a standard accretion disk around a stellar mass black hole or a neutron star at a radius of-104-5 Rg,indicating that the mass accretion rates in the accretion flow either correlate over a large range of radii at a given time or correlate over a long period of time at a given *** the accretion geometry is a two-flow geometry composed of a sub-Keplerian inflow or outflow and a disk flow in the LH state,the disk flow with a radius up to-105 Rg would have contributed to the nearly instantaneous non-thermal radiation directly or indirectly,and therefore affects the time when the state transition occurs.

关键词： accretion disks black hole physics star:individual(Aquila X-1 GX 3.9-4 4U 1705-44)

Hard X-ray lags of Cygnus X-1 on short timescales

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Science china(physics,Mechanics & Astronomy) 2010年第S1期53卷 150-152页

作者： JIN Jing1,LU Yu2,3.QU JinLu2 & li tipei1,2 1 department of Engineering {3. & center for Astro{3.,tsinghua university,Beijing 100084,china 2 Key Laboratory of Particle Astro{3.,Institute of High Energy {3.,Chinese Academy of Sciences,Beijing 100049,china 3.Graduate university of Chinese Academy of Sciences,Beijing 100049,china department of Engineering physics & center for Astrophysics Tsinghua University Beijing 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

Calculating the time lags over different timescales using the cross-correlation technique may lead to a biased estimate of small *** a timescale for lightcurve binning,we propose to subtract the local average instead of the global average during the cross-correlation,in order to filter variations on timescales larger than the bin *** new method allows us to make an unbiased estimate of the time lags using RXTE/PCA data on timescales as small as-5 ms,where the Fourier technique becomes *** calculate the time lag spectra of Cygnus X-1 at different spectral states with the new method,and find that the source appears to have similar X-ray lags on small timescales independent of its spectral states.

关键词： spectral lags Cygnus X-1 data analysis

Global analysis theory of climate system and its applications

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Chinese Science Bulletin 2003年第10期48卷 1034-1039页

作者： li Jianping1,2 & CHOU Jifan2,3.1. LASG, Institute of Atmospheric physics, Chinese Academy of Sciences, Beijing 100029, china 2. {3. of Atmospheric Sciences, Lanzhou university, Lanzhou 73.000, china 3. Training center for china Meteorological Administration, Beijing 100081, china LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China department of Atmospheric Sciences Lanzhou University Lanzhou 730000 China Training center for china Meteorological Administration Beijing 100081 China

The idea and main theoretical results of the global analysis theory of climate system are briefly summarized in this paper. A theorem on the global behavior of climate system is given, i.e. there exists a global attractor in the dynamical equations of climate, any state of climate system will be evolved into the global attractor as time increases, indicating the nonlinear adjustment process of climate system to external forcing. The different effects of external forcing, dissipation and nonlinearity on the long-term behavior of solutions are pointed out, and some main applications of the global analysis theory are also introduced. Especially, three applications, the adjustment and evolution processes of climate, the principle of numerical model design and the optimally numerical integration, are discussed.

关键词：整体分析理论气侯体系应用不定性计算法则气侯科学数字模型

Proton induced X-ray emission (PIXE) analysis of sources of porcelain body of Ru Guan and Jun Guan porcelains

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Science china(physics,Mechanics & Astronomy) 2006年第4期49卷 411-420页

作者： li Guoxia1, ZHAO Weijuan1, li Rongwu2, SUN Hongwei1, GUO Min1, wang Yanfang1, liU Hui1, ZHAO Qingyun3. SUN Xinmin3. ZHAO Wenjun3.& CHENG Huansheng4 1. Faculty of Physical Engineering, Zhengzhou university, Zhengzhou 450052, china 2. department of physics, Beijing Normal university, Beijing 100875, china 3. Institute of Cultural Relic and Archaeology of Henan Province, Zhengzhou 450000, china 4. Institute of Modern physics, Fudan university, Shanghai 20043., china Faculty of Physical Engineering Zhengzhou University Zhengzhou China department of physics Beijing Normal University Beijing China Institute of Cultural Relic and Archaeology of Henan Province Zhengzhou China Institute of Modern physics Fudan University Shanghai China

3. samples of Ru Guan porcelain body and 50 samples of Jun Guan porcelain body (both kinds being in different body colors) were selected with the purpose of finding out the source of raw materials and their classification relationship so as to search for ways of non-destructive discrimination. Proton induced X-ray emission (PIXE) has been applied to these samples to determine their chemical elements. The data of seven major chemical elements collected from these samples were further studied through fuzzy cluster analysis. Results indicate that the origin of raw materials of Jun Guan porcelain body samples is comparatively more concentrated in certain places, while that of Ru Guan porcelain body samples is scattered about. The places of origin of raw materials of the majority of Ru Guan and Jun Guan porcelain body samples have something in common, but some differences still exist. It might be an important way for non-destructive discrimination among Ru Guan and Jun Guan porcelains by combining PIXE with fuzzy cluster analysis.

关键词： Ru Guan and Jun Guan porcelain, source of porcelain body, PIXE, fuzzy cluster analysis, non-destructive discrimination.

The size effect on transport properties of colossal magnetoresistance materials La_(0.67)Ca_(0.3.)MnO_3

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Science china(physics,Mechanics & Astronomy) 2008年第3期51卷 251-257页

作者： li PeiGang1,2,LEI Ming1,2,GUO YanFeng2,GUO Xi2,CHEN LeiMing2, TANG WeiHua1,2,SONG PengYun3.& CHEN JinPing3.1 department of physics,{3. for Optoelectronics Materials and Devices,Zhejiang Sci-Tech university,Hangzhou 3.0018,china 2 National Laboratory for Condensed Matter physics,Institute of physics,Chinese Academy of Sciences,Beijing 100080,china 3.department of physics,Peking university,Beijing 100875,china department of physics Center for Optoelectronics Materials and Devices Zhejiang Sci-Tech University Hangzhou China National Laboratory for Condensed Matter physics Institute of Physics Chinese Academy of Sciences Beijing China department of physics Peking University Beijing China

High quality La0.67Ca0.3.MnO3.(LCMO) film was deposited via a novel pulsed electron deposition technique on SrTiO3.100) single crystal substrate. The micro-bridge with different widths was fabricated by using electron beam lithography (EBL) technique and their transport properties were studied. For the micro-bridges with width of 2 and 1.5 μm,the insulator-to-metal transition temperature (TP) keeps un-changed compared with the film. For the micro-bridges with width of 1 μm,the TP shifts towards the lower temperature by 50 K. When the width decreases down to 500 nm,the insulator-to-metal transition disappears. The magnetoresistance be-havior of these micro-bridges was studied,and the results show that the low field magnetoresistance (LFMR) decreases and the high field magnetoresistances (HFMR) keep almost unchanged as the width of micro-bridge is reduced.

关键词： colossal magnetoresistance pulsed electron deposition electron beam lithography electrical transport properties