光纤中心位置偏差对光谱观测结果的影响

本文详细计算了在不同的观测条件下（大气视宁度,天光背景）对于不同的观测对象（椭圆星系,旋涡星系和恒星等）光纤定位中心位置偏差对光谱观测结果的影响,根据ＬＡＭＯＳＴ的主要设计参数,给出了在不同条件下观测所得信噪比的具有数值结果,本文同时也给出了采用不同光纤尺寸对观测结果的影响。     

大气折射对大视场多目标光纤光谱观测的影响

大气折射从两个方面影响大视场多目标光纤光谱的观测：一是大气较差折射，二是由大气折射引起的大气色散。本定量地分析了这些影响。给出其对一具有５°视场，位于北纬４０．４°的望远镜在不同纬度时影响的大小。     

LAMOST系统中光纤定位板观测效率的仿真研究

讨论了在ＬＡＭＯＳＴ系统的光纤定位板上光纤的几种可行的分布方案,及各方案所能达到的观测率（即覆盖率）,并通过计算机仿真对几种方案进行比较．     

大气折射对大视场多目标光纤光谱观测的影响

大气折射从两个方面影响大视场多目标光纤光谱的观测：一是大气较差折射，二是由大气折射引起的大气色散．本文定量地分析了这些影响，给出其对一具有５°视场、位于北纬４０．４°的望远镜在不同纬度时影响的大小．     

南京大学太阳塔CCD成像光谱观测系统和初步观测结果

本文介绍南京大学太阳塔的ＣＣＤ成像光谱观测系统的结构，工作方式，给出了该系统的一些性能测试结果，作为应用该系统的实例，文中给出了根据该系统观测的二维光谱资料，经处理得到的一个Ｈａ耀斑在线心和不同偏带处单色像的变化过程，该耀斑的亮度场轮廓图和速度场轮廓图。     

LAMOST系统中光纤定位板观测效率的仿真研究

讨论了在ＬＡＭＯＳＴ系统的光纤定位板上光纤的几何可行的分布方案,及各方案所能达到的观测率（即覆盖率）,并通过计算机仿真对几种方案进行比较。     

光谱波长位置的确定

波长位置在光谱工作中至关重要。本文讨论和介绍了利用恒星光谱谱线，夜天光谱线，大气吸收线及摄谱仪标准谱灯谱线确定波长位置的方法。     

超新星SN1993J的光谱观测

SN1993J was first discovered by a Spanish amateur astronomer F. Garcia in NGC3031 (M81) on March 28, 1993. It's the closest supernova in the northern hemisphere since 1937. Because of its many special properties, it drove attentions of astronomers when it was discovered.     

云南天文台厚片CCD光谱观测系统

云南天文台的厚片CCD光谱观测系统筹备于1986年4月,1987年10月正式开题研制。经过两年的艰苦工作,终于研制成功,并于1989年10月在云台一米望远镜折轴摄谱仪上进行试观测,取得了令人满意的效果。该系统读出噪声低,暗流小,无干涉条纹,大大提高观测极限星等,是天文光谱观测研究的理想仪器,也是我国第一套厚片CCD系统。 本文主要从使用者角度出发,描述了仪器的结构、特性及其应用软件,并给出部分观测结果。     

Nova Oph 1994光谱观测研究

用２．１６ｍ望远镜及其卡焦光谱仪对ＮｏｖａＯｐｈ１９９４进行了一系列的光谱观测，其早期光谱中出现的大量ＦｅＩＩ线表明它是一颗ＦｅＩ型新星，而它的发射线的多峰结构在其他ＦｅＩＩ型新星中是不多见的．我们根据得到的光谱和从国际互联网络（Ｉｎｔｅｒｎｅｔ）得到的测光资料，讨论了它的光谱特征和演化．     

Spectroscopic Observations of the 2011 Draconids Meteor Shower

Some past October Draconid shower meteoroids fell apart in a spray of fragments at the end of their trajectory before slowing down, from which it was concluded that these were among the most fragile meteoroids known. In those instances, the dust could not be reliably traced to a particular return of the parent comet 21P/Giaconini-Zinner. On October 8th, 2011, Earth was predicted to transverse the 1900 A.D. dust ejecta of the comet. In 1900, the comet’s perihelion distance first moved significantly inwards to the Sun and ejection conditions could have been unusual. An airborne observing campaign was organized, with several teams contributing imaging and spectrographic cameras to study the manner in which these meteoroids released the volatile element sodium during the ablation process in the Earth’s atmosphere. IMCCE, ESA, and the SETI Institute contributed spectrographic cameras based on low-light WATEC 902H2 Ultimate, low-light LCC1, and GenII XX1332 image intensified cameras. An outburst was observed, much as predicted. Despite a lack of bright meteors, a total of 15 Draconid spectra were recorded. All show evidence of an early release of sodium. The loss of sodium was observed to coincide with the formation of a distinct wake of fragments. The observations show that 21P/Giacobini-Zinner ejected fragile meteoroids during the return in 1900. Those grains may have lost some sodium even before impacting Earth.     

The Effect of Lunisolar Precession on Pulsar Observations

In the measurements of pulsars’ periods and their rates of change there exists the effect of lunisolar precession. Via the analysis of this effect, we find that it can affect the accurate measurements of the periods of certain pulsars. An investigation of the periods of 1771 pulsars reveals that the measured periods of 81 pulsars suffer the influence of lunisolar precession in the range of the accuracy of measurements. With the improvement of the precision of measurements of pulsars’ periods and their change rates, this effect should get the corresponding corrections.     

Spectroscopic Observations of the Ee Cep Eclipse in 2003

High-resolution spectroscopy during the eclipse of EE Cep was obtained and presented for the first time. The star’s spectroscopic behaviour can be roughly interpreted as a partial eclipse of the high luminosity Be primary and its emitting gaseous ring by the semi-transparent gaseous envelope around an invisible, opaque secondary, most probably a dark disk. This paper is based on spectroscopic observations from Asiago (Italy), DDO (Canada), Rozhen (Bulgaria), SPM (Mexico), Terskol (Russia) and Torun (Poland) observatories.     

狐狸座PU(PU Vul)的光谱观测及其双星性质的初步讨论

我们从1981年9月至1983年12月对PU Vul进行了光谱观测,本文描述了其主要光谱特征及其变化。1981年9月PU Vul的光谱上只有吸收线,1982年10月出现很强的H_α发射线,1983年9月1日又出现H_β发射线,1983年10月H_α和H_β变得更强,11月发射线开始变弱,12月H_β发射线似已消失,但H-α发射线还是很强。整个观测期间该星光谱型基本与F型巨星相近。 这颗星很可能是一颗变化特别慢的慢新星,而且可能是由一颗M型巨星和一颗低光度的热子星组成的双星。     

Spectroscopic Observations of the Star Formation Regions in Nearby Galaxies

In recent years the number of worldwide 8∼10 m-class ground-based telescopes is continually increased, the 4 m-diameter or smaller telescopes have become the small and medium-sized telescopes. In order to obtain some noticeable scientific results by using these existing small and medium-sized telescopes, we have to consider very carefully what we can do, and what we can not. For this reason, the Time Allocation Committee of the 2.16 m telescope of the National Astronomical observatories of China (NAOC) has decided to support some key projects since 2013. The long-term project “Spectroscopic Observations of the Star Formation Regions in Nearby Galaxies” proposed by us is one of three key projects, it is supported by the committee with 30 dark/grey nights in each of three years.     

EUV Spectroscopic Observations of Spray Ejecta from an X2 Flare

An X2.3 class flare was reported on 10 April 2001 in AR 9415. A halo coronal mass ejection (CME) was associated with this flare. The Coronal Diagnostic Spectrometer (CDS) on board the Solar and Heliospheric Observatory (SOHO), which was running in its daily synoptic mode, recorded a very high-velocity ejection of plasma associated with this activity. The spatial scanning and spectral capabilities of CDS allow the measurement of both transverse and line-of-sight velocities. Components of the plasma, as seen in emission from Ov at around 2.5×10⁵ K, reached transverse velocities in excess of 800 km s^–1. The nature of the spectral line profiles suggests that a rotational motion of ±350 km s^–1 was superimposed upon the general outward expansion of approximately 150 km s^–1. The ejection detected using CDS was found to have a constant acceleration and is thought to be a spray of plasma with a helical structure driven by the magnetic topology.     

Stray-Light Effect on Magnetograph Observations

To examine the stray-light effect in magnetograph observations, we have determined the point spread functions of the vector magnetograph mounted on the Japanese Solar Flare Telescope based on two indirect methods, one analyzing the solar limb intensity profile, and the other using the Fourier power spectra of photospheric intensity distributions. Point spread functions consist of two parts: a blurring part which describes seeing and small-spread-angle stray light, and a scattering part which describes large-spread-angle stray light. The FWHM spatial resolution is typically 3.0, and the amount of scattered light is about 15% on clear days. We find that the blurring part is well described by a Moffat function whose Fourier transform is given by an exponential function. Our results indicate that polarization measurements of low-intensity magnetic elements like sunspots may be significantly underestimated due to the large-spread-angle stray light, and polarization measurements of magnetic elements which are smaller than 5–7 appear to be disturbed by small-spread-angle stray light.     

Spectroscopic Observations of New Galaxies with a UV Excess. III

The results of the spectroscopic observation of 23 galaxies with a UV excess from Kazarian's lists are presented. The spectra were obtained on the 2.6-m telescope of Byurakan Observatory with a Byu FOSC-2 camera. Two grisms, red and green, were used in the observations. Emission lines are observed in the spectra of 21 of the galaxies.     

类太阳色球活动恒星的高色散光谱观测和锂丰度

基于对9颗类太阳色球活动恒星高信噪比的高色散光谱观测, 测量了这些恒星锂线(入 = 6707.8 A'')的等值宽度, 计算了这些恒星表层锂元素丰度. 通过研究这些类太阳色球活动恒星锂丰度和X射线光度之间的关系, 发现X射线光度 强的类太阳色球活动恒星锂丰度值大于X射线较弱的恒星. 也就是说活动性较强的类太阳色球活动恒星其锂丰度较高, 活动性较弱的类太阳色球活动恒星其锂丰度较低. 考虑到主序的类太阳恒星锂元素和恒星自转速度随着恒星年龄的增加逐渐减少, 以及随着类太阳色球活动恒星自转速度的减小, 色球活动又逐渐变弱. 因此类似于锂丰度, 类太阳色球活动恒星自转速度的大小和恒星的 活动水平也同样可以表明恒星的年龄.     

High-dispersion Spectroscopic Observations of the T Tauri-type Stars with Weak Emission Lines

By using the 2.16 m telescope of Xinglong Observing Station of National Astronomical Observatories and its high-dispersion spectrograph, the high-dispersion spectroscopic observations of six T Tauri-type stars with weak emission lines (i.e., weak-line T Tauri-type stars, abbreviated as WTTS) were carried out. The lithium abundances of these weak-line T Tauri-type stars are calculated and the relationships of the lithium abundances with the rotation periods as well as the amplitudes of light variations of these stars are discussed. It is found by this study that the lithium abundance for the weak-line T Tauri-type stars with fast rotations tends to be less than that of those with slow rotations. However, for all these weak-line T Tauri-type stars, the lithium abundances have no conspicuous correlation with the amplitudes of light variations of these stars in the V waveband.