Be星ζTau的光谱研究  

A Spectroscopic Study of the Be Star ?Tau

作　　者：郭玉莲 

出　　处：《紫金山天文台台刊》1994年第1期67-68,共2页

摘　　要：A long sequence of observations of ( Tau obtained using the grating spectrograph at the 60 / 90 cm Schmidt telescoope during 1978 Dec.-1990 Feb. and the All-Fiber-Coupler grating CCD spectrograph at the 216 cm telescope after 1990 at the Xing-long Station of Beijing Observatory is presented. The reciprocal linear dispersions of the spectra were 17 A/mm, 50 A/mm and 96 A/mm. In order to study spectroscopic behaviour in detail, we measure the radial velocities of the shell absorption lines and the equivalent width and V/ R ratio of the Hα emission line. The results show that:1. The variations of the radial velocity of the shell absorption lines appeared cycle in 1978-1985. First cycle ceased around 1982 but second one lasted shorter and the amplitude was less. During 1986-1990, the velocity values conspicuously diminished and the cyclic variation also disappeared. It is a pity that we locked the radial velocity material since 1990.2. The variations of the V / R ratio of Hα is in phase with the radialA long sequence of observations of ( Tau obtained using the grating spectrograph at the 60 / 90 cm Schmidt telescoope during 1978 Dec.-1990 Feb. and the All-Fiber-Coupler grating CCD spectrograph at the 216 cm telescope after 1990 at the Xing-long Station of Beijing Observatory is presented. The reciprocal linear dispersions of the spectra were 17 A/mm, 50 A/mm and 96 A/mm. In order to study spectroscopic behaviour in detail, we measure the radial velocities of the shell absorption lines and the equivalent width and V/ R ratio of the Hα emission line. The results show that: 1. The variations of the radial velocity of the shell absorption lines appeared cycle in 1978-1985. First cycle ceased around 1982 but second one lasted shorter and the amplitude was less. During 1986-1990, the velocity values conspicuously diminished and the cyclic variation also disappeared. It is a pity that we locked the radial velocity material since 1990. 2. The variations of the V / R ratio of Hα is in phase with the radial velocity curve of the shell absorption lines before 1982. The V/R ratio fluctuated in an irregular manner during 1983-1987. The cyclic changes of V/ R ratio reappeared after 1987. 3. The Hαprofiles usually exhibited two emission peaks separated by an absorption core, but sometimes (for example, at the end of 1982, 1987 and 1990) the Hα profile did appear as a single emission either with some asymmetry or with complicated structure. It appears that the shape and structure of Hα are related to the cyclic variation of the V / R ratio. 4. The equivalent width of the Hα emission decreased gradually from 29A in 1978-79 to 6A in 1987-88, and then increased rapidly to 24A in 1992. Evidently the Hα emission was stronger in intensity in the presence of the V / R cych'c variations than in their absence. 5. me variation of the peak-separation of Hα were small in 1978-1982 and after 1990, but its amplitude became evidently larger during the 1983-1989. In addition to th

关 键 词：BE星 光谱 ζTau 

分 类 号：P145.4[天文地球—天体物理]