Aldas, Franklin, Zenteno, Alfredo, Gomez, Facundo A., Hernandez-Lang, Daniel, Carrasco, Eleazar R., Vega-Martinez, Cristian A., Castellon, J. L. Nilo2024-11-272024-11-272023/10/010035-8711http://dx.doi.org/10.1093/mnras/stad2261https://publicacionesabiertas.userena.cl/handle/123456789/145Merging of galaxy clusters are some of the most energetic events in the Universe, and they provide a unique environment to study galaxy evolution. We use a sample of 84 merging and relaxed SPT galaxy clusters candidates, observed with the Dark Energy Camera in the 0.11 < z < 0.88 redshift range, to build colour-magnitude diagrams to characterize the impact of cluster mergers on the galaxy population. We divided the sample between relaxed and disturbed, and in two redshifts bin at z = 0.55. When comparing the high-z to low-z clusters we find the high-z sample is richer in blue galaxies, independently of the cluster dynamical state. In the high-z bin, we find that disturbed clusters exhibit a larger scatter in the red sequence, with wider distribution and an excess of bluer galaxies compared to relaxed clusters, while in the low-z bin we find a complete agreement between the relaxed and disturbed clusters. Our results support the scenario in which massive cluster halos at z < 0.55 galaxies are quenched as satellites of another structure, i.e. outside the cluster, while at z >= 0.55 the quenching is dominated by in situ processes.COLOR-MAGNITUDE RELATION, COOL-CORE CLUSTERS, STAR-FORMATION, X-RAY, RICH CLUSTERS, STELLAR LOCUS, EVOLUTION, POPULATIONS, SUBSTRUCTURE, CALIBRATIONArticle