Mitchell Institute for Fundamental Physics & Astronomy
College Station, Texas 77843
Theories of galaxy formation and evolution are tested by our a growing knowledge of low-mass galaxies. Much of the progress has been made studying the closest of satellites whose histories are inextricably linked to their massive host galaxy. Finding isolated galaxies to populate the faint-end of the luminosity function outside our group environment means looking farther afield – a task which has proven unavoidably problematic due to the intrinsic faintness of the systems.
Finally, through concerted efforts, we are beginning to find, explore, and characterize very low-mass galaxies that are still gas-rich and forming stars. The physical properties of these galaxies lie below many thresholds from theoretical predictions and allow us to address numerous questions about galaxy evolution at the faint-end of the luminosity function such as: How does re-ionization impact star formation in low-mass halos? Do high-mass stars readily form at extremely low SFRs? What does chemical evolution look like in a very low-mass galaxy? In this talk, I will discuss recent discoveries of gas-rich, star-forming, very low-mass systems, and what we are learning about galaxy formation and evolution at the faint-end of the luminosity function.