Franklin AldásAlfredo ZentenoFacundo A GómezDaniel Hernandez-LangEleazar R CarrascoCristian A Vega-MartínezJ L Nilo Castellón2024-05-232024-05-232023-07-26Franklin Aldás, Alfredo Zenteno, Facundo A Gómez, Daniel Hernandez-Lang, Eleazar R Carrasco, Cristian A Vega-Martínez, J L Nilo Castellón, Clash of Titans: the impact of cluster mergers in the galaxy cluster red sequence, Monthly Notices of the Royal Astronomical Society, Volume 525, Issue 2, October 2023, Pages 1769–1778, https://doi.org/10.1093/mnras/stad22611365-2966https://conocimientoabierto.online/handle/123456789/35Merging 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.en