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Projection Effects on Physical Parameters Obtained from Solar Vector Magnetograms

chinese Journal of Astronomy and Astrophysics 2002年第2期2卷 174-182页

作者： hui li purple mountain observatory, chinese academy of sciences, nanjing {3. national Astronomical Observatories, chinese academy of sciences, beijing 100012 purple mountain observatory Chinese Academy of Sciences Nanjing 210008 []National Astronomical Observatories Chinese Academy of Sciences Beijing 100012

Projection effects in Huairou solar vector magnetograms are corrected by transferring or mapping the observed vector magnetogram in the image plane to the heliographic plane (planar correction) and to the heliospheric coordinate system (spherical correction). The magnetograms after the correction are considerably dif- ferent. The planar correction and the spherical correction lead to slightly different magnetic configurations, especially when the active region involved is far from the disk center. We also discuss the effects of the corrections on magnetic activity pa- rameters, such as magnetic shear, current helicity, etc. It is shown that the neutral line is obviously distorted after the mapping. The mapping generally decreases the average shear angle on the neutral line by several degrees when the active region is in the eastern hemisphere, and increases it when in the western hemisphere. In most of the cases studied, the correction reduces the current helicity imbalance, and sometimes even changes its sign. It is found that the current helicity imbalance may change its sign in its evolution when there are apparent fluxes emerging from the lower photosphere. The corrections increase the noise level of Bz greatly, and decrease the noise level of B~ slightly. The accuracy of the magnetic field measure- ment at Huairou is estimated to be better than 20 G and 150 G for the longitudinal and the transverse component, respectively.

关键词： Sun: magnetic fields ─Sun: activity ─Sun: photosphere

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A Note on the Mixing Length Theory and Massive Star Evolution

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chinese Journal of Astronomy and Astrophysics 2001年第1期1卷 50-56页

作者： li-Cai Deng and Da-Run Xiong ( beijing Astronomical observatory,{3., beijing 100012 purple mountain observatory,{3., nanjing210008 national Astronomical Observatories,{3., Beij CAS-Peking University Joint beijing Astrophysical Center Beijing 100871

In this paper, we investigate the problem of supersonic convection caused by the application of the usual Mixing Length Theory (MLT), and give a modification to the original expression of the MLT. In the case of the usual MLT, a zone of supersonic convection exists when the stellar model goes into yellow-red supergiant phase. When the modification is applied, the models of late type supergiants possess shallower convective envelopes for a given temperature compared with the normal formalism of the MLT. Therefore the stellar models made with our new formalism move to lower effective temperature by 100-400 K depending on the luminosity of the star. Such a modification does not affect the convective envelope structure of lower luminosity late type stars, as both expressions of the MLT give the same result. In these stars.

关键词： convection - stars: supergiants - stars: massive stars - stars: evolution

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On the Evolution of the Lower Energy Cutoff of Nonthermal Electrons in Solar Flares

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chinese Journal of Astronomy and Astrophysics 2002年第2期2卷 103-105页

作者： Wei－QunGan You－Pingli 等 purplemountainobservatory ChineseAcademyofSciencesNanjing210008 nationalAstronomicalObservatories ChineseAcademyofSciencesBeijing100012

Using the method recently developed by Can et al. (2001a, 2002), We investigate the time variation of the lower energy cutoff (Ec) of nonthermal electrons for three BATSE/CGRO hard X-ray events. The result shows that Ec changes with time, from smaller before the peak flux, to larger at the peak, and then back to smaller after the peak. Such a variation of Ec, being a preliminary conclusion for the first time, should be checked in the future by using data with a higher energy resolution.

关键词： Sun: hard X-rays─Sun: gamma-rays─Sun: flares─Sun: particles

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On the Lower Energy Cutoff of Nonthermal Electrons in Solar Flares

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chinese Journal of Astronomy and Astrophysics 2001年第5期1卷 453-459页

作者： Wei－QunGan You－Pingli 等 purplemountainobservatory ChineseAcademyofSciencesNanjing210008 nationalAstronomicalObservatories Ch

A quantitative method to determine the lower energy cutoff (Ec) of power-law electron beams is established. We apply this method to the 54 hard X-ray events observed with BATSE/Compton Gamma Ray observatory (CGRO). The results show that about 75% of the observed broken double power-law spectra of hard X-rays can be explained by a lower energy cutoff in the power-law electron beams. The values of Ec, varying among the flares, are all greater than the usually accepted 20 keV! On average, E~ is about 69 keV. So high a lower energy cutoff of nonthermal electrons implies that nonthermal electrons might not be as important in powering solar flares as was previously thought. Further significance of this finding is discussed.

关键词： Sun: hard X-rays - Sun: gamma-rays - Sun: flares - Sun: particles TheSun

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Optical results of the black hole microquasar SS 43.

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Science China(Physics,Mechanics & Astronomy) 2010年第S1期53卷 153-156页

作者： li hui1,2 & YAN JingZhi1,3.1 purple {3. observatory,chinese academy of sciences,nanjing 210008,China 2 Graduate University of chinese academy of sciences,beijing 100049,China 3.Service d’Astrophysique,CEA Saclay and University Paris Diderot,91191 Gif-sur-Yvette,France 1. purple mountain observatory Chinese Academy of Sciences Nanjing 210008 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. Service d’Astrophysique CEA Saclay and University Paris Diderot 91191 Gif-sur-Yvette France

We present optical spectroscopic observations of SS 43. during different precessional and orbital *** 2004,2007 and 2008 data provide us a good chance to study the variability of the Hα line at different orbital phases for nearly the same disk *** data show that the Hα of SS 43. usually had a symmetric profile between orbital phases 0.25-0.75,while an asymmetric structure with a strong red peak was observed for other orbital *** suggest that the orbital variability of Hα emission is connected with accretion flow from the donor star to the accretion *** addition,we attribute the dramatic increase of Hα emission during our 2007 observational run,which had a time scale of one day,to the emergence of strong jets.

关键词： high-mass X-ray binary black hole spectroscopy outflow wind relativistic jet

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An alternative evolution scenario for OAO 1657-415 and IGR J18483.03.1

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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 {3. 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 J18483.03.1 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

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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 52.3.°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 1.3. 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

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关于太阳底部贯穿对流区的延伸程度

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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 3.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

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边缘耀斑中HeI 1083.的加宽计算

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天文学报 2002年第1期43卷 41-47页

作者：黎辉尤建圻中国科学院紫金山天文台南京210008 中国科学院国家天文台北京100012

讨论了ＨｅＩ１０８３０Ａ的Ｄｏｐｐｌｅｒ和Ｓｔａｒｋ加宽机制以及各种加宽参数的计算，并得到以下一些结论：辐射阻尼对ＨｅＩ１０８３０Ａ的加宽作用与Ｄｏｐｐｌｅｒ效应相比可以忽略；在公认的耀斑电子密度（Ｎｅ＝３... 详细信息

讨论了ＨｅＩ１０８３０Ａ的Ｄｏｐｐｌｅｒ和Ｓｔａｒｋ加宽机制以及各种加宽参数的计算，并得到以下一些结论：辐射阻尼对ＨｅＩ１０８３０Ａ的加宽作用与Ｄｏｐｐｌｅｒ效应相比可以忽略；在公认的耀斑电子密度（Ｎｅ＝３．２ ×１０１３ｃｍ－３）的情况下，所有阻尼项均不可能产生可以觉察的加宽；直到Ｎｅ＝１０１５ｃｍ－３，各种阻尼对线心半宽的增加都不起作用，其值最多在１０－３的量级，因此；线心都可以看作是Ｄｏｐｐｌｅｒ加宽；当Ｎｅ＞１０１４ｃｍ－３时，Ｓｔａｒｋ加宽，特别是电子碰撞的Ｓｔａｒｋ加宽将在ＨｅＩ１０８３０Ａ的加宽中起主要作用；如要Ｓｔａｒｋ加宽谱线的线翼比纯Ｄｏｐｐｌｅｒ加宽大１－２倍，则阻尼加宽半宽与。可以相比拟；如果用Ｓｔａｒｋ加宽来解释１９８９年边缘耀斑的观测轮廓，则电子密度将达１０～（１７）ｃｍ－３，与氦原子的碰撞阻尼（γ３）造成的加宽对Ｉ１２和Ｉ３两分量明显不同，它们对Ｉ１２的影响比对Ｉ３的影响大近一个量级，我们的观测显示Ｉ１２和Ｉ３线翼的延伸基本一样，因而我们的观测

关键词：太阳耀斑谱线加宽激发电离氢线加宽机制

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大质量恒星演化研究

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天文学进展 2004年第4期22卷 296-307页

作者：田斌邓李才熊大闰中国科学院国家天文台北京100012 中国科学院紫金山天文台南京210008

由于高光度和高质量损失率等特性,大质量恒星在星系形成和演化等现代天体物理学的研究中扮演着重要的角色。自上世纪中叶以来,恒星物理研究揭示了大质量恒星内部结构和演化的主要特性,并且构造了一些大质量恒星的演化模型。然而,近年来... 详细信息

由于高光度和高质量损失率等特性,大质量恒星在星系形成和演化等现代天体物理学的研究中扮演着重要的角色。自上世纪中叶以来,恒星物理研究揭示了大质量恒星内部结构和演化的主要特性,并且构造了一些大质量恒星的演化模型。然而,近年来对大质量恒星的观测表明,已有的这些理论演化模型与观测结果之间存在着严重的分歧。在主导大质量恒星演化最主要因素(即质量损失、内部对流等问题)的处理上,现有的理论有很大的缺陷。综述了目前对上述这些问题的研究现状,并探讨了今后的研究方向。

关键词：天体物理学大质量恒星综述赫罗图对流质量损失

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