4 pages, 2 figures. To appear in "Tumbling, twisting, and winding galaxies: Pattern speeds along the Hubble sequence", E. M. Corsini and V. P. Debattista (eds.), Memorie della Societa` Astronomica Italiana
We investigate the effect of dust on the observed rotation rate of a stellar bar as measured by application of the Tremaine & Weinberg (TW) method. As the method requires that the tracer satisfies the continuity equation, it has been applied largely to early-type barred galaxies. We show using numerical simulations of barred galaxies that dust attenuation factors typically found in these systems change the observed bar pattern speed by 20-40%. We also address the effect of star formation on the TW method and find that it does not change the results significantly. This suggests that applications of the TW method can be extended to include barred galaxies covering the full range of Hubble type.
The Local Tremaine-Weinberg Method for Galactic Pattern Speed: Theory and its Application to IllustrisTNG
National Astronomical Observatories Chinese Academy of Sciences(中国科学院国家天文台);School of Astronomy and Space Science University of Chinese Academy of Sciences(中国科学院大学天文与空间科学学院);Innovation Academy for Microsatellites Chinese Academy of Sciences(中国科学院微小卫星创新研究院)
The Role of Baryonic and Dark Matter in Bar Kinematics
Dunlap Institute for Astronomy & Astrophysics, University of Toronto(多伦多大学邓普尔天文学与天体物理研究所);Department of Astronomy, Westlake University(西湖大学天文系);Westlake Institute for Advanced Study(西湖高等研究院);School of Mathematics, Statistics and Physics, Newcastle University(纽卡斯尔大学数学、统计与物理学院);Oxford Astrophysics, Department of Physics, University of Oxford(牛津大学物理系牛津天体物理学);Department of Astrophysics and Planetary Science, Villanova University(维拉诺瓦大学天体物理学与行星科学系)
MaNGA项目已经获得了数千个邻近星系的IFU数据,包括棒星系。利用IFU提供的二维光谱和运动学信息,我们可以测量棒星系的斑图速度,它决定了棒星系的动力学。我们应用Tremaine \& Weinberg提出的非参数方法估计了53个棒星系的条形图速度,这是迄今为止以这种方式研究的最大样本。我们的样本来自MaNGA第一次公开数据发布,作为SDSS Data Release 13的一部分,主要根据杆和盘之间的轴比和位置角差,而运动学数据来自后来的SDSS Data Release 14。我们已经使用了光度图像的光度位置角和恒星速度图的运动位置角来推导图案速度。结合三个独立的酒吧长度测量和圆速度从牛仔裤各向异性建模(JAM),我们还确定了无量纲比$\cal{R}$的共转半径的酒吧长度。我们发现,星系的位置角是主要的不确定性,在确定的酒吧模式的速度。运动学位置角比光度学位置角导致更少的超快棒,这可能是由于测量运动学位置角的方法。我们研究了$\cal{R}$值对星系性质的依赖性,例如JAM模型中的暗物质分数和恒星星族合成(SPS)中的恒星年龄和金属丰度。钢筋长度与钢筋强度之间存在正相关关系:钢筋越长,钢筋强度越高。然而,没有发现其他显著的相关性,这可能是由于推导$\cal{R}$值时的误差,或者是由于星系棒复杂的形成和减速过程。
Cluster-centric trends in bar size and pattern speed: the case of Abell 2199
Indian Institute of Astrophysics(印度天体物理研究所);Pondicherry University(本地治里大学);Nicolaus Copernicus Astronomical Center, Polish Academy of Sciences(波兰科学院尼古拉·哥白尼天文中心)