Star formation in distant red galaxies: Spitzer observations in the Hubble Deep Field-South

Webb, TMA; van Dokkum, P.; Egami, E; Fazio, G.; Franx, M; Gawiser, E; Herrera D.; Huang, JS; Labbé I.; Lira, P; Marchesini D.; Maza, J; Quadri, R; Rudnick, G; van der Werf, P

Abstract

We present Spitzer 24 μm imaging of 1.5<z<2.5 distant red galaxies (DRGs) in the 10′ × 10′ extended Hubble Deep Field-South of the Multiwavelength Survey by Yale-Chile. We detect 65% of the DRGs with K AB < 23.2 mag at S24μm ≳ 40 μJy and conclude that the bulk of the DRG population is dusty active galaxies. A mid-infrared (MIR) color analysis with IRAC data suggests that the MIR fluxes are not dominated by buried AGNs, and we interpret the high detection rate as evidence for a high average star formation rate of (SFR) = 130 ±30 M⊙ yr -1. From this, we infer that DRGs are important contributors to the cosmic star formation rate density at z ∼ 2, at a level of ∼0.02 M⊙ yr-1 Mpc-3 to our completeness limit of KAB = 22.9 mag. © 2006. The American Astronomical Society. All rights reserved.

Más información

Título según WOS: Star formation in distant red galaxies: Spitzer observations in the Hubble Deep Field-South
Título según SCOPUS: Star formation in distant red galaxies: Spitzer observations in the hubble deep field-south
Título de la Revista: ASTROPHYSICAL JOURNAL
Volumen: 636
Número: 1
Editorial: IOP PUBLISHING LTD
Fecha de publicación: 2006
Página de inicio: L17
Página final: L20
Idioma: English
URL: http://stacks.iop.org/1538-4357/636/i=1/a=L17
DOI:

10.1086/499805

Notas: ISI, SCOPUS