Galaxies often eject large amounts of gas and dust in outflowing galactic winds, which are a crucial element in how galaxies evolve with cosmic time. These galactic outflows explain why galaxies form relatively few stars, compared to the amount of potential fuel available for star formation. They are required by theoretical models to correctly match the observed distributions of masses and star formation rates in galaxies, yet they remain poorly understood. This project will test the extent to which stars can create such winds. Investigators will determine the physical properties of outflows in galaxies that are undergoing a burst of star formation. This project will determine the physical characteristics of both the stars in the galaxies and the outflows they are driving. These galaxies likely represent a crucial phase in the creation of massive galaxies as they consume gas and shut down the future formation of stars. This project will train undergraduate and graduate students in research and implement outreach activities that will connect K-12 classrooms across the country with professional astronomers through in-class video discussions and follow-up reflection and assessment.
Feedback in the form of outflowing gas and dust is a crucial aspect of galaxy evolution, explaining why galaxies form relatively few stars, compared to the baryon budget of the Universe. Galactic outflows are prevalent in star-forming galaxies and likely regulate and eventually shut off star formation. Despite the critical importance of feedback to the galaxy evolution process, its physical mechanisms remain poorly understood. This project will test the limits of stellar feedback by characterizing the physical properties and determining the space density of compact starburst galaxies that exhibit the fastest outflows (>1000 km/s) and highest star formation rate surface densities known. This project will determine physical characteristics of both the dusty starburst cores of these galaxies as well as the multi-phase outflowing gas. These results will constrain the physical drivers of these extreme outflows, as well as their impact on their host galaxies. This project aims to fully characterize the nature of the outflows, test a time sequence for the shutdown of star formation and the development of feedback, and place these galaxies in the broader context of massive galaxy formation. This project will also support the research efforts of multiple undergraduate students, as well as two graduate students, and will support outreach efforts to connect K-12 students with research by bringing professional astronomers into classrooms via in-class video discussions and follow-up reflection and assessment.
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.
