PI: Jessica Rosenberg, George Mason University, firstname.lastname@example.org
Address: Department of Physics and Astronomy, 4400 University Drive, MS 3F3, Fairfax, VA 22030, USA
CoI: Andrew West, MIT
Title: Determining the Baryonic Properties of Low Redshift Galaxies
Abstract: This proposal is part of a large scale study of galaxies selected independently by their neutral gas content (ALFALFA, \hi 21 cm) and their stellar content (SDSS, optical) within the same volume of space. This sample will produce the best measurement of how baryons are distributed in galaxies in the local Universe and place important constraints on (Lambda) CDM simulations, models of star formation, and the feedback processes that are responsible for the evolution of galaxies. In order to achieve the goals of this project, a detailed understanding of the joint optical and \hi galaxy selection function is required. Our proposed observations will allow us to determine the fraction of galaxies in our volume (v<9000 km/s) that (1) are below the surface brightness limit for SDSS spectroscopy (\Sigma_r_petro=24.5), and (2) are ``good" matches between ALFALFA sources and SDSS photometric sources. These observations will also allow us to derive star-formation rates and rough metallicities for a unique sample of low surface brightness galaxies for which SDSS spectroscopy does not exist. Because this population contains optically and \hi-selected low surface brightness galaxies we will be able to contrast the star-forming properties, metallicities, and dark matter fractions for these two populations.
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