Program: GS-2022B-Q-203

We have identified a three-component protocluster at z=3.7. In the central group of galaxies, we identified at least one massive quiescent galaxy and a quiescent galaxy that also contains an active galactic nucleus, maybe responsible for the quenching of the star formation. This group of galaxies is located in the highest density peak of the entire structure. We want to investigate any signs of interaction among the three components and whether the two most external ones are likely to fall into the central one. Therefore, we ask for GMOS spectroscopy to estimate precisely the redshift and the velocity dispersion of the protocluster members.