标题： 双核星系的二维光谱学 显示英文标题

标题： Two-dimensional spectroscopy of double-barred galaxies

摘要： 我们描述了一组棒旋星系的光谱观测结果，这些星系的内核区域显示出一种通常称为次级棒的等亮度线扭曲现象。 从6米特殊天体物理天文台望远镜的二维光谱中，我们得到了电离气体和恒星的视线速度场以及恒星的视线速度弥散场。 我们检测到电离气体的各种非圆周运动：大尺度棒内的径向流动，在NGC 3945中心气体与恒星的反向旋转，NGC 5850中的极性气体盘等。 我们对光学和近红外图像（包括地面观测和哈勃太空望远镜观测）的分析显示五个目标存在核区小螺旋结构。 图像中内（次级）棒的存在对核区气体和恒星的动力学没有影响。 因此，与普遍看法相反，次级棒并不是一个动力学上解耦的星系结构。 我们得出结论，所谓的双棒星系并不是一个单独的星系类型，而是具有明显不同核区形态的天体组合。 显示英文摘要

摘要： We describe the results of our spectroscopy for a sample of barred galaxies whose inner regions exhibit an isophotal twist commonly called a secondary bar. The line-of-sight velocity fields of the ionized gas and stars and the light-of-sight velocity dispersion fields of the stars were constructed from two-dimensional spectroscopy with the 6m Special Astrophysical Observatory telescope. We detected various types of non-circular motions of ionized gas: radial flows within large-scale bars, counter-rotation of the gas and stars at the center of NGC 3945, a polar gaseous disk in NGC 5850, etc. Our analysis of the optical and near-infrared images (both ground-based and those from the Hubble Space Telescope) revealed circumnuclear minispirals in five objects. The presence of an inner (secondary) bar in the galaxy images is shown to have no effect on the circumnuclear kinematics of the gas and stars. Thus, contrary to popular belief, the secondary bar is not a dynamically decoupled galactic structure. We conclude that the so-called double-barred galaxies are not a separate type of galaxies but are a combination of objects with distinctly different morphology of their circumnuclear regions.