Observations to Constrain the Origins of Hot Gas Between Galaxies and Clusters of Galaxies Across Cosmic Time

Cornell University, Ithaca NY

Investigators

Abstract

This project addresses the question of why galaxies look the way they do throughout the history of our universe. It will focus on the warm/hot gas that surrounds galaxies and provides them with fuel to form new stars. There is only incomplete theoretical understanding of the physical processes within galaxies that heat and alter this surrounding gas. This project will measure the imprint of this gas on leftover photons from the big bang which will provide new and critical information on the physics of these processes. This project will also run a pilot program to spark the interests of preschoolers in astronomy at two Agri-Business Child Development (ABCD) centers. The ABCD program offers comprehensive early childhood education to low-income families where both parents are agriculturally employed. This project will constrain feedback processes in galaxies using cross-correlation measurements from large-scale structure surveys and cosmic microwave background (CMB) experiments. Feedback processes play an important role in theories of galaxy formation and evolution. They are thought to regulate star formation in galaxies and affect the large-scale distribution of matter in our universe. An essential aspect of feedback not well understood is its impact on the reservoirs of warm/hot ionized gas that surrounds galaxies, the circumgalactic medium (CGM), which provides galaxies with new or recycled material to form new generations of stars. This project uses observations of additional fluctuations in the CMB (specifically the Sunyaev-Zeldovich effects) to probe the thermodynamic history of the CGM and provide essential information on the role of feedback in galaxy formation and evolution. 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.