标题： 变星V1027 Cyg（= IRAS 20004+2955）大气的光学谱和运动状态的新情况 显示英文标题

标题： New in the optical spectrum and kinematic state of the atmosphere of the variable V1027\,Cyg (= IRAS 20004+2955)

摘要： 基于使用6米望远镜的NES阶梯光谱仪进行的高分辨率光谱观测，我们研究了冷超巨星V1027 Cyg的大气层和包层的光谱特征和速度场，这是红外源IRAS 20004+2955的光学对应体。 首次在恒星光谱中检测到强金属吸收线及其离子（SiII、NiI、TiI、TiII、ScII、CrI、FeI、FeII、BaII）核心的分裂。 这些线条的宽轮廓中含有一个稳定的弱发射，其位置可视为系统速度Vsys=5.5 km/s。 通过对称的低强度和中等强度吸收线，发现了由于脉动引起的振幅为5-6 km/s的小幅度径向速度变化。 在恒星光谱中观察到由于线心畸变导致的H$\alpha$谱线的长波长位移。 在红色光谱区域识别出许多弱的CN分子线以及具有P Cyg轮廓的KI 7696 \AA 线。 从对称金属吸收线和CN线测得的径向速度的一致性表明，CN光谱是在恒星大气中形成的。 我们还识别出许多弥漫星际带（DIBs），它们在光谱中的位置，Vr(DIBs)=$-12.0$ km/s，与银河系本地臂中的星际介质速度相对应。 显示英文摘要

摘要： Based on high-resolution spectroscopy performed with the NES echelle spectrograph of the 6-m telescope, we have studied the peculiarities of the spectrum and the velocity field in the atmosphere and envelope of the cool supergiant V1027 Cyg, the optical counterpart of the infrared source IRAS 20004+2955. For the first time, a splitting of the cores of strong absorptions of metals and their ions (SiII, NiI, TiI, TiII, ScII, CrI, FeI, FeII, BaII) has been detected in the stellar spectrum. The broad profile of these lines contains a stable weak emission in the core whose position may be considered as the systematic velocity Vsys=5.5 km/s. Small radial velocity variations with an amplitude of 5-6 km/s due to pulsations have been revealed by symmetric low- and moderate-intensity absorptions. A long-wavelength shift of the H$\alpha$ profile due to line core distortion is observed in the stellar spectrum. Numerous weak CN molecular lines and the KI 7696 \AA\ line with a P Cyg profile have been identified in the red spectral region. The coincidence of the radial velocities measured from symmetric metal absorptions and CN lines suggests that the CN spectrum is formed in the stellar atmosphere. We have also identified numerous diffuse interstellar bands (DIBs) whose positions in the spectrum, Vr(DIBs)=$-12.0$ km/s, correspond to the velocity of the interstellar medium in the Local arm of the Galaxy.