磁对流湍流对太阳P模振动的影响(英文)     

毕少兰 《紫金山天文台台刊》2003,(2)

为了进一步探索太阳对流区的物理性质 ,我们利用高精度N的日震观测数据来研究太阳内部扰动磁场对低阶太阳P模振动的影响。对于一个时间相关的MHD湍流源 ,我们给出了导致频率变化的各种可能性。如果只考虑磁扰动的贡献 ,不同值的振动模的频率变化仅只是涨落磁场能谱的函数。我们发现频率的变化随着太阳内部磁场强度增加而变大 ,并且和太阳活动周期密切相关。我们的计算表明太阳磁活动导致的频率变化可达 0 .3μΗz。  相似文献   

恒星辐射不透明度对赫罗图中蓝回绕的影响(英文)     

王菲鹿 《紫金山天文台台刊》2003,(2)

使用不同的恒星辐射不透明度数值 ,对 5至 9个太阳质量恒星的演化模型进行计算 ,来研究辐射不透明度对赫罗图中蓝回绕的影响。结果表明在赫罗图中 ,使用OPAL不透明度值的恒星演化迹中存在着蓝回绕。而且 ,随着辐射不透明度的增加 ,蓝回绕会快速收缩直至消失  相似文献   

采矿区地层移动GPS动态监测数据的小波分析   总被引：4，自引：2，他引：2  

郑作亚  黄珹  卢秀山  张飞鹏 《大地测量与地球动力学》2003,23(3):107-111

地下煤炭资源的开采会引起岩层和地表移动。为研究开采引起的地形变规律，用小波理论对兖煤集团东滩煤矿的GPS动态变形监测资料进行多尺度一维分解、阈值选择和自动消噪等分析，提取了变形的主要因素，说明了小波分析的有效性和可行性。  相似文献   

用太阳系主要天体的位置建立特大地震的时间预测模型   总被引：5，自引：0，他引：5  

李勇 《天文学报》2003,44(4):363-368

根据某类事件发生时太阳系主要运动天体的位置，通过对其历史资料的归算，尝试并设计出一种具有普适性的事件时间预测模型．以1900-1980年间全球所有8级及以上的99次地震为例，定义与天体特征位置(视黄经)相关的发震率，初步建立预测发震时刻的概率曲线．指出这可能成为研究地震预报问题的新途径．  相似文献   

关于CCD平场快门效应的改正及有关问题   总被引：4，自引：0，他引：4  

姚保安  林清 《天文学报》1997,38(3):312-323

本文对文献中报道的两种测定快门效应改正的方法进行了讨论．我们指出，对反光镜卡焦，即使面光源本身亮度分布均匀，照射在ＣＣＤ上的辐射也可以不均匀，允许有一个二维分布。但如果这种亮度的相对分布在晨昏蒙影过程中也变化，则Ｓｕｒｍａ方法的应用便要受到影响，而这是许多人忽略的．从单纯测定快门改正函数的角度看，圆顶平场法测定更简单准确．可惜，大多数情况下精确改正快门效应的目的是同时得到精确的平场．如果要求１％或更高精度的平场，单测定快门改正还不够．对每架给定的反光镜，如何测定平场本身都是需要仔细研究的事． 作为例子，给出了佘山１．５６米反光镜加Ｔｈｏｍｓｏｎ ＲＣＣＤ（１０２４ ｘ １０２４像元）的快门改正测定．  相似文献   

RT Leonis Minoris： an Unstable W Ursae Majoris System with a Spotted Component     

Yu-Lan Yang  Qing-Yao LiuNational Astronomical Observatories  Yunnan Observatory  Chinese Academy of Sciences  Kunming  United Laboratory of Optical Astronomy  Chinese Academy of Sciences 《中国天文和天体物理学报》2004,4(6):553-562

Complete BV light curves of the W UMa type binary RT LMi are presented. From the observations, four times of minimum light were determined. Based on the new times of minimum light and those collected from the literature, changes in the orbital period of the system were found and analyzed with Kalimeris et al.'s method. The result shows that the orbital period possibly oscillates with a cycle of about 64 years and an amplitude of 1.2 × 10-6 days. The present CCD photometric observations reveal that the light curves are obviously asymmetrical, and show a positive O'Connell effect, while the light curves obtained in 1982 exhibit a negative O'Connell effect. The present light curves were analyzed by means of the latest version of the Wilson-Devinney code, which was also used to correct the photometric effects, including the distortion on the radial-velocity curves obtained by Rucinski et al. The following absolute dimensions have been derived: MI -1.28 ±0.08 M⊙, M2 = 0.48 ±0.06 M⊙, R1 = 1.28 ±0.06 R⊙,  相似文献   

A Study on the Recovery and Classification of Meteorites from the Mt. Grove Region of Antarctica     

Jian-ZhongLiu  Yong-Liao Zou  Chun-Lai Li  Lin Xu  Zi-Yuan OuyangNational Astronomical Observatories  Chinese Academy of Sciences  Beijing  jzliu@bao. ac. cnInstitute of Geochemistry  Chinese Academy of Sciences  Guiyang 《中国天文和天体物理学报》2004,4(2)

The Antarctic Continent has become the largest natural preservatory of meteorites in the world because of its unique geographical position and climatic conditions. Mt. Grove is located in the inland area of the Antarctic Continent where the conditions are favorable for the preservation of meteorites. During China's 15th, 16th and 19th Antarctic Scientific Explorations a large number of meteorites were recovered in the Mt. Grove region. Especially during the 19th Exploration in 2002/03 a total of 4448 meteorites were recovered, which at one stroke put China among countries that have recovered most numbers of meteorites. Here, we report mainly the results of microscope and electron microprobe studies of 28 meteorites recovered during the 16th Exploration. The meteorites are chemically classified based on their mean Fa contents of olivine, mean Fs contents of low-Ca pyroxene and abundances of Fe-Ni metal. We also give a brief account of the meteorite recovery during the three Explorations and of some preli  相似文献   

东营凹陷东辛2-4井上新世至全新世天文地层研究     

YAO Yi-min )  XU Dao-yi )  ZHANG Hai-feng )  HAN Yan-ben )  ZHANG Shou-peng )  YIN Zhi-qiang )  HE Qing-fang )  BIAN Xue-mei ) ) Geological Scientific Research Institute of Shengli Oilfield Company  SINOPEC  Dongying    ) Institute of Geology  China Earthquake Administration  Beijing    ) National Astronomical Observatories  Chinese Academy of Sciences  Beijing 《地层学杂志》2007,(Z2)

东辛2-4井钻取岩芯0—530.1m,明化镇组上段的上亚段至平原组划分为18个层,其中,下更新统平原组一段(简称平一段)的底作为第四系下界;同时进行了古地磁研究,测定出布容、松山、高斯和吉尔伯特等4个极性时。由于天文地层研究的需要,对90年代古地磁的年龄与"国际地层表"(2004)对比,作了相应调整,确定井深242.5m处的年龄为781ka,274.5m处的为2581ka,452.0m处的为3596ka和529.5m处的为4493ka,井深242.5m和452.0m这两个界线的年龄值作为天文地层计时的标定。研究大致分为两步:①以磁化强度(MI)数值曲线的频谱和小波分析,选定平原组一段102.4m周期和明化镇组上段68.36m周期分别对应于天文偏心率404ka旋回,求出了堆积速率为0.1584mm/a和0.1692mm/a及其他各层位的年龄:井深274.5m处上新统明上(上)亚段顶界的年龄为2546ka,平一段底界的年龄是970ka,不整合的延续时间大约为1.6Myr。②推测明上(上)亚段顶2546—1806ka期间可能沉积了129m地层;而在1806—908ka期间,由于构造活动上升,把原沉积又剥蚀掉了,形成井深274.5m处的一个大的不整合面,对储层孔隙的扩张和压实有重要影响,成为最后二次烃源物质的卸载和封堵。  相似文献   

星系中巨分子云的形成与演化     

张同杰  宋国玄 《天文学进展》1996,(4)

星系中的巨分子云(GMCs)是恒星形成的主要区域,因此它的形成和演化对于星系的演化是至关重要的。本文中将介绍分子云的基本特性、分子云之间的碰撞和巨分子云的形成、碎裂和寿命以及其他环境因素,如旋臂扰动、较差自转等在巨分子云的形成和演化中的作用。同时也探讨在采用数值模拟研究巨分子云演化时所取分子云数目的影响。  相似文献   

Spectroscopic study of globular clusters in the halo of M31 with the Xinglong 2.16 m telescope     

Zhou Fan    Ya-Fang Huang  Jin-Zeng Li  Xu Zhou  Jun Ma  Hong Wu  Tian-Meng Zhang  Yong-Heng Zhao  National Astronomical Observatories  Chinese Academy of Sciences  Beijing  China  Key Laboratory of Optical Astronomy  National Astronomical Observatories 《中国天文和天体物理学报》2011,(11)

We present spectroscopic observations for 11 confirmed globular clusters(GCs) of M31 with the OMR spectrograph on the 2.16 m telescope at the Xinglong site of National Astronomical Observatories,Chinese Academy of Sciences.Nine of our sample clusters are located in the halo of M31 and the most remote one is out to a projected radius of 78.75 kpc from the galactic center.For all our sample clusters,we measured the Lick absorption-line indices and radial velocities.It is noted that most GCs in our sample are ...  相似文献