共查询到20条相似文献,搜索用时 46 毫秒
1.
2.
目前太阳活动处于极小期,太阳表面的活动区磁场处于相对不活动状态。但暗条和冕洞等活动形式仍有存在。特别是极区冕洞,其性质仍有许多疑团不被人所知。例如磁场对冕洞的影响。在中低太阳纬度,冕洞出现在大块的磁场单极区。然而在高纬区情况如何呢?冕洞在极区经常存在(极区冕洞),但并不总是存在。我们曾看到美国高山天文台(HAO)于1973观测的一幅日全食照片,其南极有明显的极区冕洞,而北极区存在有纤细而美丽的冕羽。我国1968年和1980年两次日全食所观测的资料只有中内冕(R⊙—1.5R⊙以内),R⊙大于1.5R⊙的外日冕平时还只有在空间才能得到。1997年3月9日日全食是本世纪我国国土上观测日冕的良好机会,但条件限制我们不能携带专门用于日全食观测的大型设备,本文提出了一种用普通摄像机拍摄日冕像而再进行图像采集处理的方法,以获得R⊙大于等于2范围的日冕观测方案。另外在日全食观测前后,需要用同一台摄像机在同盘磁带上对黑暗进行拍摄以备暗场处理之用。再用同台摄像机和GG11滤光片在同盘磁带上对均匀天空进行拍摄以作黄光,白光平场背景之用。根据不同研究的需要,在资料处理时,应作相应的绝对定标,大气消光及位移的改正。 相似文献
3.
报导了云南天文台精细结构望远镜观测到的耀斑前兆机的日冕环的色球足点增亮和兰移现象。两个日冕环的4个足点由Yohkoh/HXH/SXT的观测研究所确认因光心斑前,色球上与日冕环足点相对应的,分立的点状亮谱斑,其偏带观测显示出兰移,表明它们是日冕环的色球足点,且表明存在着物质的预加热,以及物质从足点沿冕环上向上流动。观测还显示冕环所跨所跨越的暗条的激少达些现象清楚说明,物质沿磁力线的“蒸发”发生在耀斑 相似文献
4.
利用直接解调方法分析了COMPTEL对γ暴GRB910601的观测数据,发现该γ暴的直接解调成像定位较COMPTEL用最大似然法分析得到的结果更接近于Ulysses-BATSE系统联合定位的圆环.结果表明,采用直接解调方法对γ暴这类信噪比高、统计性差的瞬变源进行成像分析是完全可行的,而且,γ暴的成像定位精度可由此而获得提高. 相似文献
5.
报导了云南天文台精细结构望远镜观测到的耀斑前兆相的日冕环的色球足点增亮和兰移现象。两个日冕环的4 个足点由 Yohkoh/ H X H/ S X T 的观测研究所确认。在耀斑前, 色球上与日冕环足点相对应的、分立的点状亮谱斑,其偏带观测显示出兰移, 表明它们是日冕环的色球足点, 且表明存在着物质的预加热, 以及物质从足点沿冕环向上流动。观测还显示冕环所跨越的暗条的激活。这些现象清楚说明, 物质沿磁力线的“蒸发”发生在耀斑前兆相, 而且,色球磁场的剧烈变化可能是引起色球蒸发的原因之一 相似文献
6.
张澍 《中国天文和天体物理学报》1998,(2)
利用直接解调方法分析了COMPTEL对γ暴GRB910601的观测数据,发现该γ暴的直接解调成像定位较COMPTEL用最大似然法分析得到的结果更接近于UlysesBATSE系统联合定位的圆环.结果表明,采用直接解调方法对γ暴这类信噪比高、统计性差的瞬变源进行成像分析是完全可行的,而且,γ暴的成像定位精度可由此而获得提高. 相似文献
7.
低质量恒星形成区Taurus-Auriga外围区ROSAT定点观测选弱发射线T Tauri星候选体(WTTS)的光谱证认新发现4个WTTS。本给出了目标源的USNO R星等、USNO坐标(J2000)、分类光谱型、Hα发射/吸收线和富LiX射线源,包括新发现WTTS的LiI吸收线强度等参量以及WTTS的特征光谱。并利用Hipparcos星表对部分目标源进行了视差和自行的研究。另外,本第一次给出 相似文献
8.
俞志尧 《中国天文和天体物理学报》1994,(1)
我们从对Orion-KL星云中OH1665MHz脉泽的单基线干涉观测的分析中,提出一种新的外流模型,即多重分离的旋转膨胀环.这种模型与观测结果是一致的.通过对24km单基线观测得到的19个OH1665MHz脉泽斑点的相对位置图进行分析、统计、拟合和计算,得到这19个OH1665MHz脉泽斑点分别分布在三个旋转膨胀环上.这三个旋转膨胀环的视距分别为3".81,5".87,6".0;对应的环半径分别为1742,2720,2766AU;径向膨胀速度分别为7.07,16.4,26.4kms-1;旋转运动的切向线速度分别为1.55,1.23,1.21kms-1. 相似文献
9.
10.
11.
综述日冕物质抛射的观测和持性,简短的前言之后,给出CME的发现经过及统计特性,着重介绍CME与其他种类太阳活动的相关。然后介绍CME的一般特性,包括可能与CME相关的一些物理过程的观测特性。初步结论是:CME是一种演变中的磁结构现象。 相似文献
12.
经典的太阳光谱观测是一维的,它有很大的局限性。从50年代起,天文工作者采用多种方法开展二维太阳光谱观测,已经研制出一系列仪器,建立完整的资料归算程序,取得优良成果。在二维观测资料的基础上,用理论方法推出深度分布,可以得出三维的立体图像,这会成为太阳研究的主要方法之一。 相似文献
13.
14.
太阳大气磁场的研究对于太阳大气物理及太阳活动研究是十分重要的。目前探测光球以外的日够以球,过渡区磁场的几乎唯一办法,是在紧密联系其他频说段取得的信息基础上使用射电观测。根据在微波,米波段有关辐射机制和传播过程,介绍了推导磁场讯息的基本射电方法。 相似文献
15.
16.
17.
T. Venturi S. Bardelli G. Zambelli R. Morganti R.W. Hunstead 《Monthly notices of the Royal Astronomical Society》2001,324(4):1131-1146
We report and discuss the results of a 22-cm radio survey carried out with the Australia Telescope Compact Array (ATCA) covering the A3528 complex, a chain formed by the merging ACO clusters A3528–A3530–A3532 , located in the central region of the Shapley Concentration. Simultaneous 13-cm observations are also presented. Our final catalogue includes a total of 106 radio sources above the flux density limit of 0.8 mJy. By cross-correlation with optical and spectroscopic catalogues we found 32 optical counterparts, nine of them belonging to the A3528 complex.
We explored the effects of cluster mergers on the radio emission properties of radio galaxies by means of the radio luminosity function (RLF) and radio source counts. We found that the radio source counts are consistent with the background counts, as already found for the A3558 complex. The RLF for this complex is consistent, in both shape and normalization, with the general cluster luminosity function for early-type galaxies derived by Ledlow & Owen. This result is different from the one we obtained for the A3558 merging complex, the RLF of which is significantly lower than that derived by Ledlow & Owen.
We propose that the different stage of the merger is responsible for the different RLFs in the two cluster complexes in the core of the Shapley Concentration. The early stage of merger for the A3528 complex, proposed by many authors, may not yet have affected the radio properties of cluster galaxies, while in the more much advanced merger in the A3558 region we actually see the effects of this process on the radio emission. 相似文献
We explored the effects of cluster mergers on the radio emission properties of radio galaxies by means of the radio luminosity function (RLF) and radio source counts. We found that the radio source counts are consistent with the background counts, as already found for the A3558 complex. The RLF for this complex is consistent, in both shape and normalization, with the general cluster luminosity function for early-type galaxies derived by Ledlow & Owen. This result is different from the one we obtained for the A3558 merging complex, the RLF of which is significantly lower than that derived by Ledlow & Owen.
We propose that the different stage of the merger is responsible for the different RLFs in the two cluster complexes in the core of the Shapley Concentration. The early stage of merger for the A3528 complex, proposed by many authors, may not yet have affected the radio properties of cluster galaxies, while in the more much advanced merger in the A3558 region we actually see the effects of this process on the radio emission. 相似文献
18.
Jin-Zhao Yuan 《中国天文和天体物理学报》2011,(10)
The multicolor photometric observations of the neglected eclipsing binary FT Ursae Majoris (FT UMa) were obtained in 2010. The 2003 version of the Wilson-Devinney code was used to analyze the light curves in the B, V and R bands simultaneously. Based on the spectroscopic mass ratio q = 0.984 published by Pribulla et al., it is found that FT UMa is an evolved contact binary with a contact degree of 15.3%. The low amplitude of light variations, ~ 0.15 mag, arises mainly from a moderately low inclination angle... 相似文献
19.
Ho Seong Hwang † Myung Gyoon Lee 《Monthly notices of the Royal Astronomical Society》2009,397(4):2111-2122
We present the results of a study of galaxy activity in two merging binary clusters (A168 and A1750) using the Sloan Digital Sky Survey (SDSS) data supplemented with the data in the literature. We have investigated the merger histories of A168 and A1750 by combining the results from a two-body dynamical model and X-ray data. In A168, two subclusters appear to have passed each other and to be coming together from the recent maximum separation. In A1750, two major subclusters appear to have started interaction and to be coming together for the first time. We find an enhanced concentration of the galaxies showing star formation (SF) or active galactic nuclei (AGN) activity in the region between two subclusters in A168, which were possibly triggered by the cluster merger. In A1750, we do not find any galaxies with SF/AGN activity in the region between two subclusters, indicating that two major subclusters are in the early stage of merging. 相似文献