NOAO >   Observing Info >   Approved Programs >   2013A-0457

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Proposal Information for 2013A-0457


PI: David W. Atlee, National Optical Astronomy Observatory, atlee@noao.edu
Address: NOAO, 950 N. Cherry Ave., Tucson, AZ 85719, United States

CoI: Mark Brodwin, University of Missouri--Kansas City
CoI: Michael J. I. Brown, Monash University
CoI: Shane Bussmann, Harvard Center for Astrophysics
CoI: Vandana Desai, IPAC
CoI: Arjun Dey, National Optical Astronomy Observatory
CoI: Buell T. Jannuzi, Steward Observatory
CoI: Jason Melbourne, California Institute of Technology
CoI: Desika Narayanan, Steward Observatory
CoI: Tom Soifer, IPAC

Title: Extinction and Stellar Populations of Star Formation-Dominated Dust- Obscured Galaxies

Abstract: Dust-obscured galaxies (DOGs) selected on the basis of their unusually red R-[24] colors have been suggested as one class of possible progenitors for M>M^* z~ 0 elliptical galaxies. However, there is not yet a systematic study of the evolutionary states of star formation-dominated DOGs, which is necessary to measure the contribution of DOGs to the growth of massive ellipticals. \textbfWe propose 1.1 nights of NIR spectroscopy with GNIRS and 0.1 nights of visible spectroscopy with GMOS on Gemini-north to measure the Balmer decrement (H(beta)/H(alpha)) in a sample of 9 star formation-dominated DOGs. This sample spans approximately a dex in rest-frame L_8(mu) m, so it provides a representative sample of bump DOGs. We will use the measured reddening to break the degeneracy between age and reddening in stellar population synthesis models and model the broad-band spectral energy distributions. We will infer improved ages of the stellar populations in the target galaxies from these models, and we will use the results to estimate stellar masses and specific star formation rates. In combination with evolutionary models for galaxies of similar mass and redshift, our results will probe the contribution of the DOG phase to stellar mass assembly in massive ellipticals and illuminate the role of DOGs in the formation of these galaxies.


National Optical Astronomy Observatory, 950 North Cherry Avenue, P.O. Box 26732, Tucson, Arizona 85726, Phone: (520) 318-8000, Fax: (520) 318-8360



NOAO >   Observing Info >   Approved Programs >   2013A-0457

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