3-D Kinematics of Water Masers in the W 51A Region
3-D Kinematics of Water Masers in the W 51A Region
We report proper motion measurements of water masers in the massive-star forming region W51A and the analyses of the 3-D kinematics of the masers in three maser clusters of W51A (W51 North, Main, and South). In W~51 North, we found a clear expanding flow that has an expansion velocity of …