Hidden in the Haystack: Low-luminosity GCs towards the MW bulge

Recent wide-area surveys have enabled us to study the Galaxy with unprecedented detail. Even its inner regions, hidden behind dust and gas, have been partially unveiled by the current surveys. However, there is a population of low-mass globular clusters, known to be missing in existing catalogues, especially towards the Galactic bulge. I will present four new low-luminosity globular clusters located towards the bulge area using the Gaia EDR3 catalogue and later confirmed with deeper VVV survey near-IR photometry. Cluster parameters were derived, and when available, metallicities, radial velocities and orbits were determined using MUSE@VLT observations. Orbital parameters show similar signatures to known Milky Way structures like the Helmi, Sequoia or the 'high-energy' groups. This presentation will show that the Gaia proper motions, combined with the spectroscopic follow-up, were required to confirm the nature of cluster candidates towards the inner Milky Way regions, and the high stellar crowding and differential extinction may hide other low-luminosity clusters.