Collaborative Research: The Massive and Distant Clusters of WISE Survey 2

The team will search for galaxy clusters and protoclusters in the distant Universe, back to the time when the first clusters were forming, allowing for detailed studies of the most massive galaxies in the universe at the time when they were rapidly growing. The program is based upon catalogs created by NASA’s Wide-field Infrared Survey Explorer (WISE), a space-based observatory that performed an all-sky survey in the infrared. Combining the WISE data with catalogs from the Dark Energy Camera (DECam) on NSF’s Blanco telescope at Cerro Tololo Interamerican Observatory in Chile will allow the team to determine where the first clusters are forming in a 3D volume of the universe. The project also includes a joint virtual public viewing night program at both institutions using remote observing from the Rosemary Hill Observatory. This plan enables public engagement during the pandemic and will expand the reach of public observing programs in both states post-covid. This project will detect and characterize the massive galaxy cluster population at 0.5<z<2 over 10,480 sq. degrees, building upon a previous cluster survey by the same team, which focused upon galaxy clusters at z~1. The resulting cluster sample will enable detailed investigations of the evolution of massive galaxies in the most overdense environments since the epoch of peak star formation and rapid mass assembly. By extending the redshift baseline to z = 2, the project will reach into the era of protoclusters, in which the first massive clusters are just forming and embedded in larger scale protocluster environments comprised of dense filaments and less massive groups that will be accreted by the central clusters at later times. A combination of DECam and WISE data will be used to compute Bayesian photometric redshift probability distributions for the WISE galaxy sample and then to detect cluster scale overdensities within a 3-dimensional data cube. The PIs will foster the career development of the students working on this project.. The team will initiate and run a joint virtual public night program at their institutions using remote observing from the Rosemary Hill Observatory. This plan enables public engagement during the pandemic and will expand the reach of public observing programs in both states post-covid. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.