PI: Dawn Erb, University of Wisconsin Milwaukee, email@example.com
Address: Physics Department, P.O. Box 413, Milwaukee, WI 53201, USA
CoI: Max Pettini, University of Cambridge
CoI: Chuck Steidel, California Institute of Technology
Title: The Earliest Stages of Galaxy Formation: A Detailed Study
Abstract: With this proposal we continue a detailed investigation of z~2 galaxies with properties similar to those inferred for galaxies now being discovered at z~7, but which are bright enough for detailed spectroscopic study. Previous investigation of one such galaxy revealed highly unusual spectral features indicative of a hard stellar ionizing spectrum and an extremely high ionization parameter, but it is entirely unknown whether these features are broadly characteristic of young, low metallicity galaxies with little dust, or represent a brief phase in the evolution of more typical galaxies. Here we propose to obtain deep, rest-frame UV spectra of three closely associated z=2.2 galaxies whose low S/N discovery spectra contain these same unusual spectral features. We will constrain their metallicities, ionization parameters, electron temperatures, and C/O abundance, and assess the dependence of the unusual spectral features on broader galaxy properties. This will help us to understand whether these features are a signature of the earliest stages of galaxy formation, and therefore provide insight into the likely properties of galaxies now being discovered at much higher redshifts.
National Optical Astronomy Observatory, 950 North Cherry Avenue, P.O. Box 26732, Tucson, Arizona 85726, Phone: (520) 318-8000, Fax: (520) 318-8360