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An alternative evolution scenario for OAO 1657-415 and IGR J18483-0311

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Science china(Physics,Mechanics & Astronomy) 2010年第S1期53卷 130-134页

作者： liU QingZhong1,2,li hui1,3 & yan jingzhi1,2 1 purple mountain observatory,chinese academy of sciences,nanjing 210008,china 2 Service d’Astrophysique,CEA Saclay and University Paris Diderot,91191 Gif-sur-Yvette,France 3 Graduate University of chinese academy of sciences,Beijing 100049,china 1. purple mountain observatory Chinese Academy of Sciences Nanjing 210008 China 2. Service d’Astrophysique CEA Saclay and University Paris Diderot 91191 Gif-sur-Yvette France 3. Graduate University of chinese academy of sciences Beijing 100049 China

The relation between the spin period and the orbital period in high-mass X-ray binaries is ***/X-ray binaries and SG/X-ray binaries occupy different areas in Corbet's *** two SG/X-ray binaries,IGR J18483-0311 and OAO 1657-415,however,appear to occupy a transition region between Be/X-ray binaries and wind-fed SG/X-ray *** can be understood by noting that the neutron stars in the two SG/X-ray binaries have not reached their equilibrium spin periods when the donors evolved off the main ***,we provide an alternative scenario to explain their location in Corbet's diagram:the SG/X-ray binaries are the descendants of Be/X-ray binaries,*** supergiants in these systems were formed from O-type emission line stars instead of normal main-sequence ***,we suggest that there are two types of SG/X-ray binaries:one is directly evolved from a normal OB-type main sequence and neutron star system without an X-ray history,and the other evolved from a Be/X-ray binary with an X-ray history.

关键词： high-mass X-ray binary pulsar Corbet’s diagram stellar evolution

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 observatory,chinese academy of Science,nanjing 210008,china 2 Department of Astronomy,nanjing University,nanjing 210093,china purple mountain observatory 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

Comparative study of the relationships between CO isotopic luminosities and infrared luminosity for the Galactic dense cores

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Science china(Physics,Mechanics & Astronomy) 2010年第6期53卷 1169-1178页

作者： SUN yan & GAO Yu purple mountain observatory,chinese academy of sciences,nanjing 210008,china 1. purple mountain observatory Chinese Academy of Sciences Nanjing 210008 China

Combining the 12CO(1-0),13CO(1-0),and C18O(1-0) data with IRAS four band data,we here estimate the physical parameters such as size,viral mass,and CO J=1-0 isotopic and infrared luminosities for 29 dense molecular clouds from two published CO samples. We further analyze the various correlations between CO J=1-0 isotopic luminosities and infrared luminosity(star formation rate,SFR) and discuss the relationships between the molecular gas tracers and SFR. The results show that 12CO(1-0),13CO(1-0) and C18O(1-0) luminosities have tight correlations with each other. CO J=1-0 isotopic luminosities and SFR show weak correlations with larger scatter than the HCN-IR correlations of 47 dense cores in the Galaxy and 65 external star-forming galaxies. This might be interpreted as that both the SFR and star formation efficiency are mainly determined by the molecular gas at high volume density rather than high column density.

关键词： ISM molecular clouds radio lines star formation

Diffuse interstellar absorption bands

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Science china(Physics,Mechanics & Astronomy) 2009年第4期52卷 489-501页

作者： XIANG FuYuan1,2,liANG Shunlin2 & li AiGen2,3 1 Faculty of Materials,Photoelectronics and Physics,Xiangtan University,Xiangtan 411105,china 2 Department of Physics and Astronomy,University of Missouri,Columbia,MO 65211,USA 3 purple mountain observatory,chinese academy of sciences,nanjing 210008,china 1. Faculty of Materials Photoelectronics and Physics Xiangtan University Xiangtan 411105 China 2. Department of Physics and Astronomy University of Missouri Columbia MO 65211 USA 3. purple mountain observatory Chinese Academy of Sciences Nanjing 210008 China

The diffuse interstellar bands(DIBs) are a large number of absorption bands that are superposed on the interstellar extinction curve and are of interstellar origin. Since the discovery of the first two DIBs in the 1920s,the exact nature of DIBs still remains unclear. This article reviews the history of the detections of DIBs in the Milky Way and external galaxies,the major observational characteristics of DIBs,the correlations or anti-correlations among DIBs or between DIBs and other interstellar features(e.g. the prominent 2175 Angstrom extinction bump and the far-ultraviolet extinction rise),and the proposed candidate carriers. Whether they are also present in circumstellar environments is also discussed.

关键词： astrophysics interstellar matter interstellar extinction diffuse interstellar band circumstellar environment

CO observations of massive star forming regions at different evolutionary phases

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Science china(Physics,Mechanics & Astronomy) 2006年第5期49卷 626-640页

作者： CHEN Xi1,2, XU Ye1,3, SHEN Zhiqiang1,3 & li Jingjing1,2 1. Shanghai Astronomical observatory, chinese academy of sciences, Shanghai 200030, china 2. Graduate School of the chinese academy of sciences, Beijing 100034, china 3. Joint Institute for Galaxy and Cosmology, Shanghai Astronomical observatory and the University of Science and Technology of china, Shanghai 200030, china Shanghai Astronomical observatory Chinese Academy of Sciences Shanghai 200030 China Graduate School of the chinese academy of sciences Beijing 100034 China Joint Institute for Galaxy Cosmology Shanghai Astronomical Observatory the University of Science Technology of china Shanghai 200030 China

The 12CO (J=1-0), 13CO (J=1-0) and C18O (J=1-0) emissions in 9 massive star forming regions, which are believed to be at different stages of massive star formation, were mapped with the 13.7 m millimeter wave telescope at Qinghai Station of purple mountain observatory. Of the observed 9 sources, 13CO cores were detected in seven of them, and C18O cores in five of them. And only two sources associated with C18O cores and H2O masers showed the extended structures and strong outflows. This is the first detection of outflow associated with IRAS 22566+5828 in the observing field of S152/S153. The physical parameters of cores and outflows for these sources, derived from Local Thermal Equilibrium (LTE) analysis, are presented. These observing results suggest that the C18O cores will only appear when the gas density is high enough and the probability to have an outflow is very high when the clumps show the C18O and H2O maser simulta- neously.

关键词： star formation cloud core outflow H2O maser

Unusually Broadened Spectral Profiles Observed in Solar Prominences

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chinese Journal of Astronomy and Astrophysics 2004年第4期4卷 377-389页

作者： huili Jian-QiYou EijiroHiei purplemountainobservatory ChineseAcademyofSciencesNanjing210008 NationalAstronomicalobservatoryofJapan MitakaTokyo181-8588Japan

After surveying the spectra of 39 prominences observed by the Multi-channel Infrared Solar Spectrograph at purple mountain observatory and the 25 cm coronagraph at the Norikura Solar observatory, we found that about 28% of them show small spatial scale (6''–8'') and short time scale (tens of seconds to a few minutes), unusual large broadening and large shift velocities in spectral lines including Hα, Hβ, H, Ca II H, Ca II K, Ca II 8542?, He I D3 and He I 10830?. We present in detail two typical events observed respectively on 2002 May 27 and 1981 August 2. The full-width at half maximum of the widest profile of the 2001 prominence is 1.8? for Hα and 2.9 ? for He I 10830?, while that of the 1981 prominence is 5.3 ? for Hβ, 3.6 ? for Ca II K, 4.0 ? for Ca II H and 2.8 ? for He I D3. Such broadenings generally occur at a level of several-thousand kilometres above the chromosphere. Further, most of these prominences manifest a rotation of (0.4–1.35)×10-2 rads s?1 pointing to the Sun and large line-of-sight velocities of 20–200 km s?1. Some of these events correspond in time to an enhancement or a small peak in the GOES X-ray flux, indicating the existence of high energy process at work. These prominences generally display discernible changes in the Hα morphology around the time of large broadening, but do not show Hα brightening or overall eruption except for a few small surge-like events, hence, they are hardly observed in daily Hα patrols. According to the characteristics of their Hα structures and spectral properties, we infer these events are small-scale eruptions similar to nano-flares, which may contribute to the mass and energy transported into the corona. Large turbulent velocities of 25–120 km s?1 are responsible for the observed broadenings.

关键词： sun: prominences line: profiles turbulence

Primary scientific results of Chang'E-1 lunar mission

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Science china Earth sciences 2010年第11期53卷 1565-1581页

作者： OUyanG ZiYuan1,2, li ChunLai1, ZOU Yongliao1, ZHANG HongBo1, Lü Chang1, liU JianZhong1, liU JianJun1, ZUO Wei1, SU yan1, WEN WeiBin1, BIAN Wei1, ZHAO BaoChang3, WANG JianYu4, yanG JianFeng3, CHANG Jin5, WANG HuanYu6, ZHANG Xiaohui7, WANG ShiJin7, WANG Min1, REN Xin1, MU lingli1, KONG DeQing1, WANG XiaoQian1, WANG Fang1, GENG liang1, ZHANG ZhouBin1, ZHENG Lei1, ZHU XinYing1, ZHENG YongChun1, li JunDuo1, ZOU XiaoDuan1, XU Chun1, SHI ShuoBiao1, GAO YiFei1 & GAO GuanNan1 1 National Astronomical Observatories, chinese academy of sciences, Beijing 100012, china 2 Institute of Geochemistry, chinese academy of sciences, Guiyang 550002, china 3 Xi’an Institute of Optics and Precision Mechanics, chinese academy of sciences, Xi’an 710119, china 4 Shanghai Institute of Technical Physics, chinese academy of sciences, Shanghai 200083, china 5 purple mountain observatory, chinese academy of sciences, nanjing 210008, china 6 Institute of High Energy Physics, chinese academy of sciences, Beijing 100049, china 7 Center for Space Science and Applied Research, chinese academy of sciences, Beijing 100190, china 1. National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China2. Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China3. Xi’an Institute of Optics and Precision Mechanics Chinese Academy of Sciences Xi’an 710119 China4. Shanghai Institute of Technical Physics Chinese Academy of Sciences Shanghai 200083 China5. Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China6. Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China7. Center for Space Science and Applied Research Chinese Academy of Sciences Beijing 100190 China

The strategic plan for the development of the unmanned chinese Lunar Exploration Program is characterized by three distinct stages: "orbiting around", "landing on" and "returning from" the Moon. The first chinese lunar probe, Chang'E-1, which was successfully launched on October 24th, 2007 at Xichang Satellite Launch Center, and guided to crash on the Moon on March 1st, 2009, at 52.36°E, 1.50°S, in the north of Mare Fecunditatis, is the first step towards the "orbiting around" stage. The Chang'E-1 mission lasted 495 days, exceeding the expected life-span by about four months. A total of 1.37 TB raw data was received from Chang'E-1. It was then processed into 4 TB scientific data products at various levels. Many scientific results have been obtained by analyzing these data, including especially the "global lunar image from the first chinese lunar explora- tion mission". All scientific goals of Chang'E-1 have been achieved. It provides much useful materials for further advances of lunar sciences and planetary chemistry. Meanwhile, these results will serve as a firm basis for future chinese lunar missions.

关键词： lunar orbiter Chang’E-1 scientific data results

Tillage Pedogenesis of purple Soils in Southwestern china

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Journal of mountain Science 2009年第2期6卷 205-210页

作者： HE Xiubin BAO Yuhai NAN Hongwei XIONG Donghong WANG li liU yanfeng ZHAO Jingbo Institute of mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China Graduate School of the chinese academy of sciences Beijing 100049 China Shaanxi Normal University Xi'an 710062 China

Land cultivation and tillage process, and their consequent impacts on soil erosion, have been criticized as the main cause of degradation of land or soil quality. However, purple soils, classified as Regosols in FAO Taxonomy or Entisols in USDA Taxonomy, are formed from purple rocks of the Trias- Cretaceous system, have been developed or at least accelerated the development due to continual tillage operation, especially digging and ridging. The present study took micromorphological investigation on the sedimentary rocks and the soils under different operations of tillage. Results show that the purple rock of Feixiangguan Formation of the Trias system （Tlf） is the easiest to physical weathering and the most fertile soil material enriched in nutrients, and it has been, therefore, mostly cultivated and intensively tilled around the year. It has the fastest soil formation rate. Soil formation rate in the cropland with conventional tillage is higher than that in the forestiand and the grassland. It implies that the artificial brokenness and tillage disturbance play a great role in physical weathering and initiating soil formation processes.

关键词： Tillage impact pedogenesis purple soil micromorphology southwestern china

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关于太阳底部贯穿对流区的延伸程度

天文学报 2001年第2期42卷 121-124页

作者：熊大闰邓李才中国科学院紫金山天文台中国科学院北京天文台

The extension of the solar lower overshooting zone is discussed. There is no any near discontinuity of the derivatives of sound speed at the bottom of the lower overshooting zone, as described by the phenomenological non local mixing length theory. On the contrary, the temperature gradient turns smoothly from nearly adiabatic stratification into radiative one. In the lower overshooting zone the temperature gradient is sub adiabatic, but it is super radiative! Namely  rad 1.01) is around 0.63 H p (0.053 R ⊙ ).

关键词：恒星对流贯穿对流太阳恒星演化内部结构