Program: GN-2021B-Q-315

Extra tidal structures and tidal tails associated with Galactic globular clusters (GGCs) are a consequence of their interactions with the Milky Way, but the detailed dynamics remain largely unexplored. We propose to carry out a GMOS-N spectroscopic survey of stars around NGC 4147 to develop a well-sampled radial velocity map of the cluster outskirts and its well-populated tidal tails. Combined with Gaia proper motions, the resulting catalog of 3-D space motions will enable us to characterize the velocity field and model the dynamical processes at play. Detailed dynamical modeling will enable us to constrain (i) the amount of dark matter remaining in the cluster, (ii)) theoretical models of evaporation and tidal stripping, and (iii) the influence of other Galactic constituents (e.g. the bulge, bar, disk, giant molecular clouds, and dark matter subhalos) on the development and structure of tidal tails and cold stellar streams.