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Prediction method for October 2003.solar storm

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Science china(Technological sciences) 2006年第5期49卷 629-640页

作者： XIE Yanqiong1, 2, 3. WEI Fengsi1, FENG Xueshang1 & ZHONG Dingkun1, 2 1. State key laboratory of Space Weather, Center for Space Science and Applied Research, chinese academy of sciences, {3. 100080, china 2. Graduate School, chinese academy of sciences, {3. 10003., china 3. institute of Meteorology, PLA University of Science and Technology, Nanjing 211101, china State key laboratory of Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences Beijing China Graduate School Chinese Academy of Sciences Beijing China institute of Meteorology PLA University of Science and Technology Nanjing China

Aiming at two intense shock events on October 28 and 29, 2003. this paper presents a two-step method, which combines synoptic analysis of space weather ——“observing” and quantitative prediction ——“palpating”, and then uses it to test predictions. In the first step of “observing”, on the basis of observations of the solar source surface magnetic field, interplanetary scintillation (IPS) and ACE spacecraft, we find that the propagation of the shocks is asymmetric relative to the normal direction of their solar sources, and the Earth is located near the direction of the fastest speed and the greatest energy of the shocks. As the two fast ejection shock events, the fast explosion of coronal mass of the extremely high temperature, the strong magnetic field, and the high speed background solar wind are also helpful to their rapid propagation. In the second step of “palpating”, we adopt a new membership function of the fast shock events for the ISF method. The predicted results show that for the onset time of the geomagnetic disturbance, the relative errors between the observational and the predicted results are 1.8% and 6.7%; and for the magnetic disturbance magnitude, the relative errors are 4.1% and 3.1%, re- spectively. Furthermore, the comparison among the predicted results of our two-step method with those of five other prevailing methods shows that the two-step method is advantageous. The results tell us that understanding the physical features of shock propagation thoroughly is of great importance in improving the prediction precision.

关键词： solar storm, interplanetary shock, interplanetary scintillation, two-step method, ISF method.

Diagnostics for the structure of AGNs'broad line regions with reverberation mapping data:confirmation of the two-component broad line region model

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Science china(Physics,Mechanics & astronomy) 2010年第S1期53卷 196-201页

作者： ZHU Ling1 & ZHANG ShuangNan2 1 Department of Physics and Tsinghua Center for astrophysics,Tsinghua University,beijing 100084,china 2 {3. laboratory of particle astrophysics,institute of high energy Physics,chinese academy of sciences,beijing 100049,china Department of Physics and Tsinghua Center for astrophysics Tsinghua University Beijing China key laboratory of particle {3.physics Institute of High Energy Physics Chinese Academy of Sciences Beijing China

We re-examine the ten Reverberation Mapping(RM) sources with public data based on the two-component model of the Broad Line Region(BLR).In fitting their broad Hβ Mlines,six of them only need one Gaussian component,one of them has a double-peak profile,one has an irregular profile,and only two of them need two components,i.e.,a Very Broad Gaussian Component(VBGC) and an Inter-Mediate Gaussian Component(IMGC).The Gaussian components are assumed to come from two distinct regions in the two-component model;they are the Very Broad Line Region(VBLR) and the Inter-Mediate Line region(IMLR).The two sources with a two-component profile are Mrk 509 and NGC *** time lags of the two components of both sources satisfy tIMLR/tVBLR=V 2VBLR/V 2IMLR,where tIMLR and tVBLR are the lags of the two components while VIMLR and VVBLR represent the mean gas velocities of the two regions,supporting the two-component model of the BLR of Active Galactic Nuclei(AGNs).The fact that most of these ten sources only have the VBGC confirms the assumption that RM mainly measures the radius of the VBLR;consequently,the radius obtained from the R-L relationship mainly represents the radius of ***,NGC 4051,with a lag of about 5 days in the one component model,is an outlier on the R-L relationship as shown in Kaspi et al.(2005);however this problem disappears in our two-component model with lags of about 2 and 6 days for the VBGC and IMGC,respectively.

关键词： broad line region AGN Reverberation Mapping cross correlation

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 & Center for astrophysics,Tsinghua University,beijing 100084,china 2 {3. 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 {3.physics 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

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 energy Physics,{3., beijing 10003., china Graduate School of{3., beijing 10003., china institute of high energy Physics 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 high energy cosmic ray disappears naturally in the framework of the de Sitter kinematics.

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

GRB 090423.Marking the death of a massive star at z=8.2

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Science china(Physics,Mechanics & astronomy) 2010年第S1期53卷 64-68页

作者： LIN Lin1,LIANG EnWei2 & ZHANG ShuangNan3.1 Department of Physics and Center for astrophysics,Tsinghua University,beijing 100084,china 2 Department of Physics,Guangxi University,Nanning 53.004,china 3.key laboratory of particle astrophysics,institute of high energy Physics,chinese academy of {13.,beijing 100049,china Department of Physics and Center for astrophysics Tsinghua University Beijing China Department of Physics Guangxi University Nanning China key laboratory of particle {3.physics Institute of High Energy Physics Chinese Academy of Sciences Beijing China

GRB 090423.is the new high-z record holder of Gamma-ray bursts(GRBs) with *** present a detailed analysis of both the spectral and temporal features of GRB 090423.observed with Swift/BAT and Fermi/*** find that the T90 observed with BAT in the 15-150 keV band is 13.2 s,corresponding to-1.4 s at z=*** once again gives rise to the issue of whether the progenitors of high-z GRBs are massive stars or mergers since the discovery of GRB 080913.at z=*** comparison with the T90 distribution in the burst frame of the current redshift-known GRB sample,we find that it is marginally grouped into the long group(Type II GRBs).The spectrum observed with both BAT and GBM is well fitted by a power-law with exponential cutoff,which yields an Ep=(50.4±7.0) *** event satisfies the Amati-relation well for Type II GRBs within their 3. uncertainty *** results indicate that this event would be produced by the death of a massive *** on the Amati-relation,we derive its distance modulus,which follows the Hubble diagram of the concordance cosmology model at a redshift of-8.2.

关键词： gamma-ray bursts high energy phenomenon cosmology

Properties of the 3.2^-[521] band in the odd-N rare-earth nuclei

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Science china(Physics,Mechanics & astronomy) 2011年第S1期54卷 37-43页

作者： CHEN Liang1,2, ZHOU XiaoHong1,2, ZHANG YuHu1, ZHANG ShuangQuan3.& ZHU LiHua4 1institute of Modern Physics, chinese academy of sciences, Lanzhou 73.000, china 2Graduate University of chinese academy of sciences, beijing 100049, china 3.tate key laboratory of Nuclear Physics and Technology, School of Physics, Peking University, beijing 100871, china 4china institute of Atomic energy, beijing 102413. china institute of Modern Physics Chinese Academy of Sciences Lanzhou China Graduate University of chinese academy of sciences Beijing China State key laboratory of Nuclear Physics and Technology School of Physics Peking University Beijing China china institute of Atomic energy Beijing China

high-spin states in 161Er have been studied experimentally via the 150Nd(16O, 5n) reaction at a beam energy of 86 MeV. Three rotational bands built on the 5/2+[642], 3.2-[521], and 11/2-[505] configurations have been extended up to high-spin states, and particularly, the α = -1/2 branch of the ground state 3.2-[521] band has been revised significantly. It is found that signature inversion occurs in the 3.2-[521] band after the band crossing in 161Er. The systematics of the signature inversion associated with the 3.2-[521] configuration in the rare-earth region is discussed. The band properties are analyzed within the framework of a triaxial {3.-rotor model, and a triaxial deformation is proposed to the 3.2-[521] band.

关键词： high-spin states signature inversion triaxial particle-rotor model

Role of gallium wetting layer in high-quality ZnO growth on sapphire (0001) substrates

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Science china(Physics,Mechanics & astronomy) 2004年第5期47卷 612-620页

作者： ZENG Zhaoquan1,3. WANG Yong2, DU Xiaolong1, MEI Zengxia1, KONG Xianghe3. JIA Jinfeng1, XUE Qikun1 & ZHANG Ze2, 4 1. State key laboratory for Surface Physics, institute of Physics,{3., beijing 100080, china 2. laboratory of Electron Microscopy, institute of Physics,{3., beijing 100080, china 3. College of Physics and Engineering, Qufu Normal University, Qufu 273.65, china 4. beijing University of Technology, beijing 100022, china State key laboratory for Surface Physics Institute of Physics Chinese Academy of Sciences Beijing China College of Physics and Engineering Qufu Normal University Qufu China laboratory of Electron Microscopy Institute of Physics Chinese Academy of Sciences Beijing China beijing University of Technology Beijing China

A Ga wetting layer was used to modify the surface structure of sapphire (0001) substrate to prepare high-quality ZnO film by radio frequency plasma-assisted molecule beam epitaxy. We found that this Ga layer plays a crucial role in eliminating 3. rotation domains, controlling polarity and decreasing defect density in ZnO epilayers, as demonstrated by in situ reflection high energy electron diffraction, ex situ high resolution X-ray diffraction and high resolution cross-sectional transmission electron microscopy. Zn-polar film of ZnO was determined by convergent beam electron diffraction. A Ga bilayer model is proposed to understand the effects of the Ga wetting layer on high-quality ZnO growth.

关键词： Ga wetting layer, sapphire, polarity, defect density, zinc oxide, rf-MBE, RHEED, HRXRD, TEM, CBED.

The rms-flux relation of Cyg X-2 in the horizontal branch

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中国科学：物理学、力学、天文学英文版 2010年第S1期53卷 86-90页

作者： LI ZhiBing,LEI YaJuan,QU JinLu,ZHANG Shu & SONG LiMing key laboratory for particle {3.physics,institute of high energy Physics,chinese academy of sciences(CAS),beijing 100049,china key laboratory for particle {3.physics Institute of High Energy Physics Chinese Academy of Sciences (CAS) Beijing China

We have investigated the relation between the root mean square(rms) variability and the X-ray flux(rms-flux relation) of the Z source Cyg X-2,and as well the energy dependence based on the Rossi X-ray Timing Explorer(RXTE) *** currently focus on the horizontal branch(HB),due to the negative correlation in flux of the soft and the hard *** rms-flux correlation has energy dependence as follows:positive at hard X-rays(above 10 keV) but negative at soft X-rays(below 10 keV).This provides a feature different from the previous one,and may be suggestive of different origins of X-rays below and above 10 ***,the overall spectrum can be well fitted with a model consisting of a blackbody and Comptonization components,but the fitting results do not reveal any features around 10 keV that could account for such a change in the rms-flux relation.

关键词： accretion accretion disk—binaries:close-stars:individual(Cygnus X-2)-X-rays:binaries

The time lag spectrum of Cir X-1 on its normal branch

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Science china(Physics,Mechanics & astronomy) 2010年第S1期53卷 60-63页

作者： QU JinLu1,LU Yu1,2,DING GuoQiang3.ZHANG Fan1,LEI YaJuan1 & LI ZhiBing1 1 key laboratory for particle {3.physics,institute of high energy Physics,chinese academy of sciences,beijing 100049,china 2 Graduate University of{13.,beijing 100049,china 3.Urumqi Observatory,NAOC Urumqi 83.011,china key laboratory for particle {3.physics Institute of High Energy Physics Chinese Academy of Sciences Beijing China Graduate University of chinese academy of sciences Beijing China Urumqi Observatory NAOC Urumqi China

In the radiation-hydrodynamics model,the time lag and fractional root-mean-squared(rms) amplitude as a function of emitted photon energy should show a minimum on the normal branch *** has been seen in the Z-sources Cyg X-2 and GX ***,using the observations from the Rossi X-ray Timing Explorer(RXTE),we study the energy dependence of normal branch QPOs in the peculiar Z-source Cir *** discuss the results in the context of radiation-hydrodynamics and the Comptonization model.

关键词： Cir X-1 temporal variability QPO time lag