Radii of the Milky Way globular clusters

We make use of a homogeneous, up-to-date data set with kinematics, structural properties, current and initial masses of 156 globular clusters. In general, cluster radii increase as the Milky Way potential weakens; with the core and Jacobi radii being those which increase at the slowest and fastest rate, respectively.

We interpret this result as the innermost regions of globular clusters being less sensitive to changes in the tidal forces with the Galactocentric distance. The Milky Way gravitational field also seems to have differentially accelerated the internal dynamical evolution of individual clusters, with those toward the bulge appearing dynamically older. Finally, we find a subpopulation consisting of both compact and extended globular clusters (as defined by their r_h_/r_J_ ratio) beyond 8 kpc that appear to have lost a large fraction of their initial mass lost via disruption.