检索结果-南通市图书馆

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 2.0008 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

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

A Note on the Mixing Length Theory and Massive Star Evolution

引用

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, chinese academy of sciences, beijing 100012 purple mountain observatory, chinese academy of sciences, nanjing2.0008 national astronomical observatories, chinese academy of sciences, Beij beijing astronomical observatory Chinese Academy of Sciences Beijing 100012 national astronomical observatories Chinese Academy of Sciences Beijing 100012 CAS-Peking University Joint beijing Astrophysical Center Beijing 100871 purple mountain observatory Chinese Academy of Sciences Nanjing 210008

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

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

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

引用

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

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

On the Lower Energy Cutoff of Nonthermal Electrons in Solar Flares

引用

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

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

边缘耀斑中HeI 10830的加宽计算

引用

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

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Primary scientific results of Chang'E-1 lunar mission

引用

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 2.0008, 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 national astronomical observatories Chinese Academy of Sciences Beijing China Institute of Geochemistry Chinese Academy of Sciences Guiyang China Xi’an Institute of Optics and Precision Mechanics Chinese Academy of Sciences Xi’an China Shanghai Institute of Technical Physics Chinese Academy of Sciences Shanghai China purple mountain observatory Chinese Academy of Sciences Nanjing China Institute of High Energy Physics Chinese Academy of Sciences Beijing China Center for Space Science and Applied Research Chinese Academy of Sciences Beijing 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

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

大质量恒星演化研究

引用

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

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

有摄圆型限制性三体问题平动点稳定的充要条件及应用

引用

天文学报 2005年第1期46卷 37-45页

作者：舒斯会陆本魁陈务深刘福窑中国科学院紫金山天文台

给出了一个判断有摄圆型限制性三体问题平动点稳定性的充要条件.该条件只依赖于平动点变分方程的特征方程系数的一个简单关系,使用很方便.用所得到的条件, 讨论了任意外力摄动对经典圆型限制性三体问题三角平动点稳定性的影响和惯性阻... 详细信息

给出了一个判断有摄圆型限制性三体问题平动点稳定性的充要条件.该条件只依赖于平动点变分方程的特征方程系数的一个简单关系,使用很方便.用所得到的条件, 讨论了任意外力摄动对经典圆型限制性三体问题三角平动点稳定性的影响和惯性阻力摄动对Robe圆型限制性三体问题主要平动点的稳定性的影响.

关键词：动点充要条件平动变分方程摄动特征方程外力限制性稳定性系数

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

平动点线性稳定条件及阻力对限制性三体问题三角平动点线性稳定性的影响

引用

天文学报 2004年第3期45卷 301-309页

作者：舒斯会陆本魁刘福窑陈务深中国科学院紫金山天文台

给出了受摄限制性三体问题平动点线性稳定性的一些判断条件,条件只与相应的平动点切映像的特征方程系数有关,使用方便.用这些判断条件,讨论了一些阻力对经典限制性三体问题三角平动点线性稳定性的影响,改进了Murray等的一些结果.

关键词：天体力学限制性三体问题平动点稳定性阻力

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

New era of chinese solar instruments

引用

Science China(Technological sciences) 2023年第4期66卷 1203-1204页

作者： li Chuan TIAN hui HUANG Yu School of Astronomy and Space Science Nanjing UniversityNanjing 210023China Key Laboratory for Modern Astronomy and Astrophysics Ministry of EducationNanjing 210023China School of Earth and Space sciences Peking UniversityBeijing 100871China Key Laboratory of Solar Activity and Space Weather National Space Science CenterChinese Academy of SciencesBejing 100190China national astronomical observatories Chinese Academy of SciencesBejing 100101China purple mountain observatory Chinese Academy of SciencesNanjing 210034China

As China’s first comprehensive satellite dedicated for solar physics,the Advanced Space-based Solar observatory(ASO-S)[1,2]was successfully lifted off from Jiuquan Satellite Launch Center at 7:43 on 9 October,2022(China Standard Time,CST).ASO-S,dubbed“Kuafu-1”(Kuafu was a giant in chinese mythology who never stopped chasing the Sun).

关键词： lift Launch Solar

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：