Collaborative Research: Testing the Lambda Cold Dark Matter Paradigm with Dwarf Satellites of Low-mass Galaxies

Association Of Universities For Research In Astronomy, Inc., Tucson AZ

Investigators

Abstract

All large galaxies, like our own Milky Way, are surrounded by many smaller "satellite" companion galaxies. Scientists have recently discovered tiny satellite galaxies around the Large Magellanic Cloud, a small Milky Way companion galaxy. Current predictions are not able to reproduce the numbers and properties of these satellite galaxies. Small "dwarf" galaxies thus challenge our understanding of the physical processes that shape galaxies. To solve the puzzle, this project explores galaxies beyond the Milky Way and its Local Group of galaxies. The investigators will test predictions by searching for the tiniest satellites around small galaxies beyond our Local Group. These satellites are predicted to be faint and can only be found using the most advanced telescopes on Earth. The properties of the new objects will be compared to satellites in our Local Group and interpreted in the context of theoretical models. The three investigators, together with a postdoctoral researcher and students, will use state-of-the-art instrumentation on large optical telescopes to perform systematic, panoramic imaging surveys of 11 sub-Milky Way-mass target galaxies. The research team will interpret this census of faint satellites with the aid of dedicated analytical models. The final goal is to inform our understanding of the galaxy formation physics at the lowest mass scales. These observations can reveal how the stellar content of dwarf galaxies relates to their dark matter halos. The results will be interpreted as a function of galaxy environment, halo mass and morphology, thus providing quantitative constraints for star formation, feedback and re-ionization prescriptions in the framework of galaxy formation models. The Investigators will use this research to increase the involvement of underrepresented minorities in astronomy by developing a support network for women in science at the University of Tampa. This will provide valuable guidance for their future careers and advise them on gender balance issues. At Ohio State University (OSU), astronomy-themed YouTube coding videos will be developed for high school students. Additionally, a peer-mentoring program led by OSU students will be supported by this program through participation in a dedicated Leadership Retreat. 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.