LEAPS-MPS: Where galaxies keep their cool in the heat: A Pathfinder to detect cool cosmic gas filaments and their effects on galaxy properties in clusters.

Cuny New York City College Of Technology, Brooklyn NY

Investigators

Abstract

On the largest scales, galaxies are found to be arranged along vast networks of filamentary structures, commonly referred to as the cosmic web, that evolved from minute density fluctuations in the very early universe. Recent work by a team including the principal investigator (PI) concluded that cool, low-turbulence gas can flow along the cosmic web and penetrate deep into galaxy clusters and shield galaxies from the hot intra-cluster medium, effectively prolonging their ability to form stars. This research program will allow (1) a more precise characterization of the filamentary "shielding" mechanism on the dynamics and star formation activity of cluster galaxies, with the added potential to (2) indirectly trace the cool gas streams themselves. This program will provide unique research and professional experiences for at least six undergraduate students from groups underrepresented in STEM, with each student acting as a mentor and role model for another student at an earlier career stage. The PI will conduct a follow-up pilot study combining a completed integral-field spectroscopic (IFS) survey of 3,068 low redshift galaxies (SAMI) with mock IFS data cubes for 150,000 galaxies generated using the Horizon-AGN cosmological simulation. The PI and her students will extend the pipeline used to create mock IFS image cubes for simulated galaxies occupying filaments and cluster environments to include newly developed quenching diagnostics. These will be used in conjunction with standard IFS measures of galactic dynamics (e.g., maps of rotational velocity, velocity dispersion, and rotation asymmetry) to find observational signatures best suited to trace galaxy-filament interactions, assess how galaxies are affected by their proximity to intra-cluster filaments, and determine how the merging status of filaments might influence the results. This LEAPS-MPS research program promises to make a significant contribution regarding the interplay between galaxies and the cosmic web. 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.