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arXiv · 1605.05314

Differences in the structural properties and star-formation rates of field and cluster galaxies at z~1

Rebecca J. Allen·Glenn G. Kacprzak·Karl Glazebrook·Kim-Vy H. Tran·Lee R. Spitler·Caroline M. S. Straatman·Michael Cowley·Themiya Nanayakkara
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Abstract

We investigate the dependance of galaxy sizes and star-formation rates (SFRs) on environment using a mass-limited sample of quiescent and star-forming galaxies with M>10^9.5 at z=0.92 selected from the NMBS survey. Using the GEEC2 spectroscopic cluster catalog and the accurate photometric redshifts from NMBS, we select quiescent and star-forming cluster (sigma=490 km/s) galaxies within two virial radius, Rvir, intervals of 0.5 1, than field star-forming galaxies. The average SFRs of star-forming cluster galaxies show a trend of decreasing SFR with clustocentric radius. The mass-normalised average SFR of cluster star-forming galaxies is a factor of 2-2.5 (7-9 sigma) lower than that of star-forming galaxies in the field. While we find no significant dependence on environment for quiescent galaxies, the properties of star-forming galaxies are affected, which could be the result of environment acting on their gas content.

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Rebecca J. Allen, Glenn G. Kacprzak, Karl Glazebrook, Kim-Vy H. Tran, Lee R. Spitler, Caroline M. S. Straatman, Michael Cowley, Themiya Nanayakkara. 2016-05-17. Differences in the structural properties and star-formation rates of field and cluster galaxies at z~1. https://doi.org/10.3847/0004-637x%2F826%2F1%2F60

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