Hidden in plain sight: Uncovering low-surface-brightness galaxies and their host dark matter halos

Greco Johnny P, Westerville OH

Investigators

Abstract

Johnny Greco is awarded an NSF Astronomy and Astrophysics Postdoctoral Fellowship to conduct a program of research and education at the Ohio State University. Greco will perform a systematic search for faint, diffuse galaxies known as low-surface-brightness galaxies (LSBGs). Using a software that he created and optimized for the detection of LSBGs, he will aim to increase the number of LSBGs in new and existing optical observational surveys. Greco will produce a public catalog of many thousands of previously unknown LSBGs spanning a wide range in properties, and he will perform detailed observations of some of these LSBGs. Results from this study will allow astronomers to understand how LSBGs form and how they fit within the cosmological context. Alongside this research, Greco will create educational projects designed to encourage high school girls to pursue careers in science and computer programming. By building an unbiased sample of LSBGs, the proposed research will elucidate formation mechanisms of giant LSBGs, which will provide important constraints on theories of galaxy formation and evolution. Furthermore, as systems predominantly composed of dark matter, LSBGs provide the most stringent tests of our current cosmological model. By combining rotation curves, globular cluster studies, and possibly a stacked weak-lensing analysis, the proposed research will constrain the dark matter distribution in these galaxies on both small and large scales. Working with an outreach program at his host institution, Greco will use his expertise in astronomical image processing and coding to design software and student projects to stimulate the interest of high school girls in science, and he will serve as a mentor to high school students interested in astronomy research. 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.