标题： 银河系的运动学结构，靠近旋臂切线处 显示英文标题

标题： Kinematic structure of the Milky Way galaxy, near the spiral arm tangents

摘要： 我们比较不同旋臂示踪物的观测径向速度，这些速度是在接近旋臂切点处测得的。 根据内旋臂入口处预测的激波，密度波理论预测了微小的差异。 在许多这些旋臂中，观测到的速度偏移证实了密度波理论的预测（脉泽速度与CO气体峰值速度之间的分离约为20 km/s）——当观测到的偏移大于误差估计时。 到达下一个旋臂的时间已给出。 显示英文摘要

摘要： We compare the observed radial velocity of different arm tracers, taken near the tangent to a spiral arm. A slight difference is predicted by the density wave theory, given the shock predicted at the entrance to the inner spiral arm. In many of these spiral arms, the observed velocity offset confirms the prediction of the density wave theory (with a separation between the maser velocity and the CO gas peak velocity, of about 20 km/s) - when the observed offset is bigger than the error estimates. The time to reach the next spiral arm is given.