NOAO >   Observing Info >   Approved Programs >   2012A-0454

# Proposal Information for 2012A-0454

PI: Kyoungsoo Lee, Yale University, soo.lee@yale.edu
Address: Physics Department, 260 Whitney Avenue, JWG 462, New Haven, CT 06511, USA

CoI: Arjun Dey, NOAO
CoI: Buell Jannuzi, NOAO
CoI: Naveen Reddy, NOAO
CoI: Anthony H. Gonzalez, U. of Florida

Title: Unveiling the Most Massive Structure at z=3.78

Abstract: In the hierarchical framework, the highest density peaks mark the sites of the earliest and largest galaxy formation. Identifying these regions at high redshift (proto-cluster'') would improve our understanding of the formation and evolution of these massive systems and their constituent galaxies. We propose to observe a massive protocluster candidate at z=3.78 using Mosaic 1.1 Imaging on the Mayall 4m telescope. Unlike many known proto-clusters, the overdensity was discovered serendipitously without any extreme sources (powerful radio galaxy or quasar) nearby, and thus will provide an ideal laboratory to study the environmental dependence of galaxy evolution. The new data will be a critical improvement over the existing data by reaching further down the steep end of the UV luminosity function, and thus will identify many more member galaxies that belong to this massive structure \it without further requiring spectroscopy. Once we quantify the extent of this overdensity and identify the members based on the proposed observations, we will investigate the effects of the large-scale environment on the properties of galaxies (physical conditions of the star formation from their UV spectra, stellar population parameters such as stellar mass and age) by directly comparing to those of field'' galaxies found from the same survey. Using existing \it Herschel data, we will also test the merger- driven starbursts'' scenario, which should be more frequent in dense environments.

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 NOAO >   Observing Info >   Approved Programs >   2012A-0454