The connection between the origins of globular clusters (GCs) and the evolution of their host galaxy

Star kinematics is directly connected to the evolution history of their host galaxy. To recover the correct kinematics, though, it is necessary to assign each star to the galaxy component it belongs to: the disk (thin or thick) or the spheroid. Performing a multiband decomposition of infrared images of NGC 3115, and planetary nebulae (PNe) as tracers of the overall stellar populations, we recovered the velocity and velocity dispersion of the thick disk and of the spheroid. We then studied the GCs population in NGC 3115. Given a GC position and velocity we can estimate its probability of belonging to the disk, to the spheroid and in general to the system. We find that most GCs are consistent of being drawn from the light weighted velocity distribution of NGC 3115 stars. Nearly half of the GCs belongs to the disk and half to the spheroid, but we don’t find any trend between their colour (b-r) or calcium triplet abundances and their kinematics