The Origin of the Large Magellanic Cloud Globular Cluster NGC 2005

Abstract

The ancient Large Magellanic Cloud (LMC) globular cluster NGC 2005 has recently been reported to have an ex situ origin, thus, setting precedents that the LMC could have partially formed from smaller merged dwarf galaxies. We here provide additional arguments from which we conclude that is also fairly plausible an in situ origin of NGC 2005, based on the abundance spread of a variety of chemical elements measured in dwarf galaxies, their minimum mass in order to form globular clusters, the globular cluster formation imprints kept in their kinematics, and the recent modeling showing that explosions of supernovae are responsible for the observed chemical abundance spread in dwarf galaxies. The present analysis points to the need for further development of numerical simulations and observational indices that can help us to differentiate between two mechanisms of galaxy formation for the LMC; namely, a primordial dwarf or an initial merging event of smaller dwarfs.

Keywords

• Large Magellanic Cloud
• Globular star clusters