Galaxy properties in different environments at z > 1.5 in the GOODS-NICMOS Survey

Ruth Grützbauch; Robert W. Chuter; Christopher J. Conselice; Amanda E. Bauer; Asa F. L. Bluck; Fernando Buitrago; Alice Mortlock

arXiv · 1011.5158

Galaxy properties in different environments at z > 1.5 in the GOODS-NICMOS Survey

Ruth Grützbauch·Robert W. Chuter·Christopher J. Conselice·Amanda E. Bauer·Asa F. L. Bluck·Fernando Buitrago·Alice Mortlock

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Abstract

We present a study of the relationship between galaxy colour, stellar mass, and local galaxy density in a deep near-infrared imaging survey up to a redshift of z~3 using the GOODS NICMOS Survey (GNS). The GNS is a very deep, near-infrared Hubble Space Telescope survey imaging a total of 45 arcmin^2 in the GOODS fields, reaching a stellar mass completeness limit of M* = 10^9.5 M_sun at z=3. Using this data we measure galaxy local densities based on galaxy counts within a fixed aperture, as well as the distance to the 3rd, 5th and 7th nearest neighbour. We find a strong correlation between colour and stellar mass at all redshifts up to z~3. We do not find a strong correlation between colour and local density, however, the highest overdensities might be populated by a higher fraction of blue galaxies than average or underdense areas, indicating a possible reversal of the colour-density relation at high redshift. Our data suggests that the possible higher blue fraction at extreme overdensities might be due to a lack of massive red galaxies at the highest local densities.

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Ruth Grützbauch, Robert W. Chuter, Christopher J. Conselice, Amanda E. Bauer, Asa F. L. Bluck, Fernando Buitrago, Alice Mortlock. 2010-11-23. Galaxy properties in different environments at z > 1.5 in the GOODS-NICMOS Survey. https://arxiv.org/abs/1011.5158

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