Kinematics of the Gould Belt Based on Open Clusters

Abstract

We have redetermined kinematic parameters of the Gould Belt using currently available data on the motion of nearby young (log t < 7.91) open clusters, OB associations, and moving stellar groups. Our modeling shows that the residual velocities reach their maximum values of -4 km/s for rotation (in the direction of Galactic rotation) and +4 km/s for expansion at a distance from the kinematic center of about 300 pc. We have taken the following parameters of the Gould Belt center: Ro=150 pc and lo=128 degrees. The whole structure is shown to move relative to the local standard of rest at a velocity of 10.7+-0.7 km/s in the direction l=274+-4degrees and b=-1+-3 degrees. Using the derived rotation velocity, we have estimated the virial mass of the Gould Belt to be 1.5E6 Solar mass.