论文标题
经典头虫的三维运动学
Three-Dimensional Kinematics of Classical Cepheids
论文作者
论文摘要
使用线性的Ogorodnikov-Milne模型用于研究银河系中经典头孢虫的三维运动学。 MR'oz等人的832个经典头虫样品。 （2019年）使用距离，视线速度和GAIA DR2目录的正确运动。头孢虫空间速度已从我们先前基于非线性旋转模型的我们发现的差分银河旋转中释放出来。基于完整的Ogorodnikov-Milne模型，涉及隔离线的速度和恒星的正确运动，我们估计了围绕银河$ y $ axis旋转的角速度，$ω_y= 0.64 \ pm0.17 $ 〜pm0.17 $ 〜km s $ s $我们认为这种旋转与银河薄磁盘的经线有关。我们的计算仅在磁盘经扭曲引起的没有变形的假设下仅使用cepheid的适当动作表明，在$ y $轴周围存在残留旋转，其角速$ω_y= 0.54 \ pm0.15 $ 〜km s $ s $ s $ s $ s $^km s $^{ - 1} $ kpc $ kpc $ kpc $^$ a a $ a a $ a a $ a a a $ a a a $ a a a $ a a a a $ a a a y a a $ a a a y a a a y a a y an a a y nocati速度$ω_x= 0.33 \ pm0.10 $ 〜km s $^{ - 1} $ kpc $^{ - 1} $。
A linear Ogorodnikov-Milne model is applied to study the three-dimensional kinematics of classical Cepheids in the Milky Way. A sample of 832 classical Cepheids from Mr'oz et al. (2019) with distances, line-of-sight velocities, and proper motions from the Gaia DR2 catalogue is used. The Cepheid space velocities have been freed from the differential Galactic rotation found by us previously based on a nonlinear rotation model. Based on a complete Ogorodnikov-Milne model, involving the line-of-sight velocities and proper motions of stars, we have estimated the angular velocity of rotation around the Galactic $y$ axis, $Ω_y=0.64\pm0.17$~km s$^{-1}$ kpc$^{-1}$. We think that this rotation is associated with the warp of the Galactic thin disk. Our calculations using only the proper motions of Cepheids under the assumption of no deformations due to the disk warp have shown the presence of a residual rotation around the $y$ axis with an angular velocity $Ω_y=0.54\pm0.15$~km s$^{-1}$ kpc$^{-1}$ and the presence of a positive rotation around the $x$ axis with an angular velocity $Ω_x=0.33\pm0.10$~km s$^{-1}$ kpc$^{-1}$.
