Characterization and Dynamics of Merging Galaxy Clusters

Wednesday, 20 February 2019 9 a.m. — 10 a.m. MST

AURA Lecture Hall

NOIRLab South Colloquia
DANIEL HERNANDEZ (Universidad de La Serena (ULS) and NOAO South Intern Student)

ΛCDM cosmological model establish that massive structures form by merging and smooth accretion of smaller structures. This model predicts that numerous galaxy clusters are in some stage of merging at any epoch. Cluster mergers provide unique environmental conditions under which galaxies are transformed. Characterize the stage of the merging event and the merging components, along with having a large sample of merging clusters, is then crucial in our understanding of these phenomena. In a pilot study we analyzed the dynamically complex system; Abell 267 (A267), a fossil system classified as non-relaxed given that it shows a projected separation between the X--ray and mass peak and the BCG. Using spectroscopically confirmed members taken from literature, we study the dynamics of the cluster in order to understand its merging stage. We recently have obtained Gemini/GMOS data for 12 clusters for which we will expand the analysis of A267, such clusters were classified as disturbed systems using the BCG-X-ray distance proxy, with data from the Dark Energy Survey. In the future, DeROSITAS data will provide optical imaging to select the BCG of dozens of thousands of clusters and groups, providing a dynamical state classification proxy and a new sample of merging candidates.