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arXiv · 0902.3997

A spectroscopic measure of the star-formation rate density in dwarf galaxies at z~1

G. T. Davies·David Gilbank·Karl Glazebrook·Richard Bower·I. K. Baldry·Michael Balogh·G. K. T. Hau·I. H. Li·P. McCarthy·S. Savaglio
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Abstract

We use a K-selected (22.5 < K_AB < 24.0) sample of dwarf galaxies (8.4 < log(M*/Msun) < 10) at 0.89<z<1.15 in the Chandra Deep Field South (CDFS) to measure their contribution to the global star-formation rate density (SFRD), as inferred from their [OII] flux. By comparing with [OII]-based studies of higher stellar mass galaxies, we robustly measure a turnover in the [OII] luminosity density at a stellar mass of M~10^10 Msun. By comparison with the [OII]-based SFRD measured from the Sloan Digital Sky Survey we confirm that, while the SFRD of the lowest-mass galaxies changes very little with time, the SFRD of more massive galaxies evolves strongly, such that they dominate the SFRD at z = 1.

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G. T. Davies, David Gilbank, Karl Glazebrook, Richard Bower, I. K. Baldry, Michael Balogh, G. K. T. Hau, I. H. Li, P. McCarthy, S. Savaglio. 2009-02-23. A spectroscopic measure of the star-formation rate density in dwarf galaxies at z~1. https://doi.org/10.1111/j.1745-3933.2009.00646.x

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