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Recent study of emission line star 3.71

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chinese Science Bulletin 1998年第6期43卷 470-473页

作者： HANG Hengrong 1,2.and XIA Jianping+1 1. Purple mountain {2., {3. academy of Sciences, nanjing 2.0008, China 2. Joint Laboratory for Optical Astronomy, {3. academy of Sciences, nanjing 2.0008, China Purple mountain {2. Chinese Academy of Sciences Nanjing China Joint Laboratory for Optical Astronomy Chinese Academy of Sciences Nanjing China

New spectral observations of 3.71 are presented. The main features of optical spectra which exhibit a lot of forbidden lines and unusual strong H-Balmer emission lines are discussed. Our data, together with its large IRAS infrared color excess and other characteristics, show evidence that the star may be a Herbig Ae/Be star rather than the optical counterpart of Be/X-ray source of 1H2.14+589.

关键词： Be/X-ray binary emission line IRAS identification Herbig Ae/Be star.

Simulation of energy and water balance in Soil-Vegetation-Atmosphere Transfer system in the mountain area of Heihe River Basin at Hexi Corridor of northwest China

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Science China Earth Sciences 2005年第4期48卷 538-548页

作者： KANG Ersi1, CHENG Guodong1, , SONG Kechao1, JIN Bowen1, , LIU Xiande3.2.3.& WANG Jinye3.1. Cold and Arid Regions Environmental and Engineering Research Institute, chinese academy of Sciences, Lanzhou 73.000, China 2. State Key Laboratory of Frozen Soil Engineering, chinese academy of Sciences, Lanzhou 73.000, China 3. academy of Water Resources Conservation Forest of Qilian mountains, Gansu Province, Zhangye 73.000, China 1. Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences 730000 Lanzhou China 2. State Key Laboratory of Frozen nSoil Engineering Chinese Academy of Sciences 730000 Lanzhou China 3. academy of Water Resources Conservation Forest of Qilian {2.s 734000 Gansu Province Zhangye China

In the mountain area of inland Heihe River Basin at Hexi Corridor of northwest China during the vegetation growing season from May to September, the Simultaneous Heat and Water (SHAW) model of Soil-Vegetation-Atmosphere Transfer (SVAT) system is applied to simulating and studying energy and water balance of the soil-residue-plant canopy layers in the Picea crassifolia forest and the grassland by the forest at the shaded slope and the grassland at the sun-facing slope. The simulation of energy balance indicates that net radiation of the grass- land at the sun-facing slope is more than that of the Picea crassifolia forest and the grassland by the forest at the shaded slope. The energy outgoing components are the first latent heat and next sensible heat from the grassland both at the shaded slope and the sun-facing slope, but those at the former are less. The energy outgoing components are the first sensible heat and next latent heat from the Picea crassifolia forest. The composition and distribution of energy in the soil-residue-plant canopy layers in the Picea crassifolia forest and the grassland by the forest at the shaded slope make the soil layer receive less energy, which therefore, especially the forest possesses the energy conditions for soil water conservation. The simulation of water balance indicates that the water loss of the grassland at the sun-facing slope is mainly caused by soil evaporation, while evapotranspiration of the Picea crassifolia forest and the grassland by the forest at the shaded slope is less than that of the grassland at the sun-facing slope. Half of the evapotranspiration of the Picea crassifolia forest and the grassland by the forest at the shaded slope is consumed by transpiration. After precipitation, the soil water storage is increased much more for the Picea crassifolia forest and also more for the grassland by the forest at the shaded slope. Therefore the shaded slope vegetation, especially the forest is favorable for soil water s

关键词： inland rivers, mountain vegetation zone, Soil-Vegetation-Atmosphere Transfer (SVAT) system, energyand water balance, simulation.

The red damping wing of Gunn-Peterson trough in the high redshift GRBs

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Science China(Physics,Mechanics & Astronomy) 2009年第9期52卷 1428-1433页

作者： XU Zhou1,2.& WEI DaMing1,3.1 Purple {2. {2., {3. academy of Sciences, nanjing 2.0008, China 2.Graduate University of {3. academy of Sciences, Beijing 100012. China 3.Joint Center for Particle Nuclear Physics and Cosmology of Purple {2. {2.-nanjing University, nanjing 2.0008, China Purple mountain {2. Chinese Academy of Sciences Nanjing 210008 China Graduate University of chinese academy of Sciences Beijing 100012 China Joint Center for Particle Nuclear Physics and Cosmology of Purple mountain {2.-{3. University Nanjing 210008 China

We calculate the red damping wing of Gunn-Peterson trough taking the evolution of the neutral fraction into consideration and take a clear look at the ionized region around the ionizing sources. We get the result that the damping wing flux feature is mainly determined by the neutral hydrogen outside the ionized bubble and the cut off in the damping wing would be useful to get the size of the ionized bubble. We also fit the red damping wing of the recently discovered high redshift GRB080913.and find that the ionized bubble is too small to create apparent cut off in the spectrum of this burst.

关键词： cosmology theory intergalactic medium gamma ray burst

Simulations for terrestrial planets formation

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Science China(Physics,Mechanics & Astronomy) 2009年第5期52卷 794-803页

作者： ZHANG Niu 1,2.&JI JiangHui 2.3.1Graduate University of chinese {2. of Sciences,Beijing 100049,China {2.,chinese {2. of Sciences,nanjing 2.0008,China 3.National Astronomical Observatories,chinese {2. of Sciences,Beijing 100012.China Graduate University of chinese academy of Sciences Beijing 100049 China Purple mountain {2. Chinese Academy of Sciences Nanjing 210008 China National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China

In this paper,the formation of terrestrial planets in the late stage of planetary formation is investigated using the two-planet *** that time,the protostar formed for about 3.Ma and the gas disk *** the model,the perturbations from Jupiter and Saturn are *** of the mass of outer planet,and the initial eccentricities and inclinations of embryos and planetesimals are also *** results show that,terrestrial planets are formed in 50 Ma,and the accretion rate is about 60%-80%.In each simulation,3.4 terrestrial planets are formed inside"Jupiter"with masses of 0.15 -3.6M⊕.In the 0.5-4 AU,when the eccentricities of planetesimals are excited,planetesimals are able to accrete material from wide radial *** plenty of water material of the terrestrial planet in the Habitable Zone may be transferred from the farther places by this *** could also happen a few times between two major planets only if the outer planet has a moderate mass and the small terrestrial planet could survive at some resonances over time scale of 10 8 *** one of our simulations,commensurability of the orbital periods of planets is very ***,a librating-circulating 3.2.configuration of mean motion resonance is found.

关键词： astrophysics exoplanet planetary formation n-body simulation

Molecular Gas and Dust in the Massive Star Forming Region S 2.0} IR

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chinese Journal of Astronomy and Astrophysics 2004年第5期4卷 440-454页

作者： Rui-Qing Mao and Qin Zeng1 Purple mountain {2., {3. academy of Sciences, nanjing 2.0008 2.National Astronomical Observatories, {3. academy of Sciences, Beijing 100012 National Astronomical Observatories CAS NAOC Beijing 100012 China

The massive star forming region S 2.0} IR is observed in the molecular lines CO J = 2.1, 3.2. NH3.(1,1), (2.2. and the 870 um dust continuum. Four submillimeter continuum sources, labelled SMM 1–4, are revealed in t... 详细信息

The massive star forming region S 2.0} IR is observed in the molecular lines CO J = 2.1, 3.2. NH3./SUB> (1,1), (2.2. and the 870 um dust continuum. Four submillimeter continuum sources, labelled SMM 1–4, are revealed in the 870 um dust emission. The main core, SMM1, is found to be associated with a deeply embedded near infrared cluster in the northeast; while the weaker source SMM2.coincides with a more evolved cluster in the southwest. The best fit spectral energy distribution of SMM1 gives an emissivity of β = 1.6, and temperatures of 3. K and 92.K for the cold- and hot-dust components. An SMM1 core mass of 2.6 M☉, and a total mass of 445 M☉ are estimated from the 870 um dust continuum emission. SMM1 is found to have a temperature gradient decreasing from inside out, indicative of the presence of interior heating sources. The total outflow gas mass as traced by the CO J = 3.2.emission is estimated to be 3. M☉. Low velocity outflows are also found in the NH3./SUB> (1,1) emission. The non-thermal dominant NH3./SUB> line width as well as the substantial core mass suggest that the SMM1 core is a ``turbulent, massive dense core', in the process of forming a group or a cluster of stars. The much higher star formation efficiency found in the southwest cluster supports the suggestion that this cluster is more evolved than the northeast one. Large near infrared photometric variations found in the source PCS-IR93. a previously found highly polarized nebulosity, indicate an underlying star showing the FU Orionis type of behavior.

关键词： ISM: jets and outflows ISM: molecules ISM: dust, extinction stars:formation ISM: individual

Numerical simulations of magnetic reconnection in the lower solar atmosphere

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Research in Astronomy and Astrophysics 2011年第2期11卷 225-236页

作者： Xiao-Yan Xu 1,2.Cheng Fang 2.Ming-De Ding 2.and Dan-Hui Gao 2.1 Purple mountain {2.,{3. academy of Science,nanjing 2.0008,China 2.Department of Astronomy,nanjing University,nanjing 2.0093.China Purple mountain {2. Chinese Academy of Science Nanjing 210008 China Department of Astronomy Nanjing University Nanjing 210093 China

Observations indicate that Ellerman bombs （EBs） and chromospheric microflares both occur in the lower solar atmosphere,and share many common features,such as temperature enhancements,accompanying jet-like mass motions,short life-time,and so *** strongly suggest that EBs and chromospheric microflares could both probably be induced by magnetic reconnection in the lower solar *** gravity,ionization and radiation considered,we perform two-dimensional numerical simulations of magnetic reconnection in the lower solar *** influence of different parameters,such as intensity of the magnetic field and anomalous resistivity,on the results are *** result demonstrates that the temperature increases are mainly due to the joule dissipation caused by magnetic *** spectral profiles of EBs and chromospheric microflares are calculated with the non-LTE radiative transfer theory and compared with *** is found that the typical features of the two phenomena can be qualitatively reproduced.

关键词： Sun: chromosphere-- Sun: photosphere -- Sun: magnetic reconnection-- Sun: numerical simulation

The approximate state transition matrix based on non-orthogonal decomposition and its application in orbit determination

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Science China(Physics,Mechanics & Astronomy) 2010年第3期53卷 555-561页

作者： CHEN WuShen1,2. MA JingYuan2. ZHANG Jing2.& LU BenKui2.1 nanjing University of Technology, nanjing 2.0009, China 2.P{2. {3. observatory, chinese academy of Sciences, nanjing 2.0008, China 1. nanjing University of Technology Nanjing 210009 China2. Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China

The Unit Vector Method (UVM) is an orbit determination method extensively applied. In this paper, the UVM and classical Differential Orbit Improvement (DOI) are compared, and a fusion method is given for the orbit determination with different kind data. Based on non-orthogonal decomposition of position and velocity vectors, an approximation scheme is constructed to calculate the state transition matrix. This method simplifies the calculation of the approximate state transition matrix, analyzes the convergence mechanism of the UVM, and makes clear the defect of weight strategy in UVM. Results of orbit the determination with simulating and real data show that this method has good numerical stability and rational weight distribution.

关键词： Unit Vector Method state transition matrix non-orthogonal decomposition

Effects of various solar indices on accuracy of Earth’s thermospheric neutral density models

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Science China(Physics,Mechanics & Astronomy) 2009年第7期52卷 1120-1128页

作者： WANG HongBo1,2.& ZHAO ChangYin1 1 Purple mountain {2., {3. academy of Sciences, nanjing 2.0008, China 2.Graduate University of {3. academy of Sciences, Beijing 100049, China Purple mountain {2. Chinese Academy of Sciences Nanjing 210008 China Graduate University of chinese academy of Sciences Beijing 100049 China

Four kinds of solar indices F10.7, E10.7, S10, Mg10 and four thermospheric neutral density models, i.e., CIRA72. DTM94, NRLMSISE00 and JB2.06, are discussed. The CHAMP accelerometer data are used to calculate thermospheric total mass density. Based on the comparison of the model densities with CHAMP observations, the effects of various indices on the model accuracy are detected. It is found that under quiet and moderate solar conditions (F10.72.0) the error’s standard deviation using E10.7 increases quickly and causes the models’ accuracy to fall down. With regard to S10, Mg10, their effects under quiet solar conditions are inconspicuous. If under active solar conditions, they can reduce the model error’s standard deviation by 5%-10%, implying that S10, Mg10 make the model error more stable. The JB2.06 model, which was constructed by multi-solar-index (F10.7, S10, Mg10), is compared with DTM94 and NRLMSISE00 based on single-solar-index. It is found that JB2.06’s accuracy is better than DTM94’s, and is close to NRLMSISE00 under the quiet solar condition. During the solar burst occurring on October 2., 2.03. JB2.06 has been in best agreement with CHAMP observations. All in all, the new indices may improve thermospheric density models’ accuracy under some special conditions. Concretely, E10.7 may reduce the average error of models and S10, Mg10 may prevent the error’s divergence.

关键词： solar radiation index CHAMP accelerometer data neutrals density model

A new class of symmetric periodic solutions of the spatial elliptic restricted three-body problem

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Science China(Physics,Mechanics & Astronomy) 2009年第9期52卷 1404-1413页

作者： XU XingBo1,2.& FU YanNing1 1 Purple mountain {2., {3. academy of Sciences, nanjing 2.0008, China 2.Graduate University of {3. academy of Sciences, Beijing 10003., China 1. Purple mountain {2. Chinese Academy of Sciences Nanjing 210008 China 2. Graduate University of chinese academy of Sciences Beijing 100039 China

We show that there exists a new class of symmetric periodic solutions of the spatial elliptic restricted three-body problem. In such a solution, the infinitesimal body is confined to the vicinity of a primary and moves on a nearly circular orbit. This orbit is almost perpendicular to the orbital plane of the primaries, where the line of symmetry of the orbit lies. The existence is shown by applying a corollary of Arenstorf's fixed point theorem to a periodicity equation system of the problem. And this existence doesn't require any restriction on the mass ratio of the primaries, nor on the eccentricity of their relative elliptic orbit. Potential relevance of this new class of periodic solutions to real celestial body systems and the follow-up studies in this respect are also discussed.

关键词： periodic orbits spatial restricted three-body problem symmetric orbits averaging