PI: Kate E. Dellenbusch, University of Wisconsin - Madison, firstname.lastname@example.org
Address: Department of Astronomy, 475 N. Charter St., Madison, WI 53706, USA
CoI: John S. Gallagher III, University of Wisconsin - Madison
CoI: Patricia M. Knezek, WIYN Observatory
Title: Oxygen Abundances and Evolutionary Paths in Starbursting Transition Dwarf Galaxies
Abstract: Dwarf galaxies show a wide range of evolutionary states, indicating that the evolution of lower mass galaxies is quite complex. For example, van den Bergh (1977) noted dwarf galaxies are typically either very actively forming stars or are inactive, with few dwarfs between these states. Is there then a population of objects in an intermediary state, and do dwarf galaxies transition over time from one state to another? Almost 30 years after van den Bergh's presentation, it still is not clear whether significant fractions of dwarf galaxies outside of clusters remain in a single morphological class or rapidly evolve from one morphology to another over time by some process such as interaction. We are studying a sample of galaxies which appear to be undergoing such a transition and may be evolving from a gas-rich actively star forming state to a gas-poor inactive one. Chemical abundances are key tracers of galaxy evolution, which we propose to exploit here. Long slit spectrophotometry will allow HII region oxygen abundances to be measured, providing an essential step towards understanding whether and how evolutionary transitions occur.
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