Answers are grounded in this paper and cite their sources.
We present the results of a spectroscopic survey with LRIS-B on Keck of more than 280 star-forming galaxies and AGNs at redshifts 1.4 ≾ z ≾ 3.0 in the GOODS-N field. Candidates are selected by their U_nGR colors using the "BM/BX" criteria to target redshift 1.4 ≾ z ≾ 2.5 galaxies and the LBG criteria to target redshift z ~ 3 galaxies; combined these samples account for ~25%-30% of the R and K_s band counts to R = 25.5 and K_s(AB) = 24.4, respectively. The 212 BM/BX galaxies and 74 LBGs constitute the largest spectroscopic sample of galaxies at z > 1.4 in GOODS-N. Extensive multiwavelength data allow us to investigate the stellar populations, stellar masses, bolometric luminosities (L_(bol)), and extinction of z ~ 2 galaxies. Deep Chandra and Spitzer data indicate that the sample includes galaxies with a wide range in L_(bol) (≃10^(10) to >10^(12) L_☉) and 4 orders of magnitude in dust obscuration (L_(bol)/L_(UV)). The sample includes galaxies with a large dynamic range in evolutionary state, from very young galaxies (ages ≃50 Myr) with small stellar masses (M* ≃ 10^9 M_☉) to evolved galaxies with stellar masses comparable to the most massive galaxies at these redshifts (M* > 10^(11) M_☉). Spitzer data indicate that the optical sample includes some fraction of the obscured AGN population at high redshifts: at least 3 of 11 AGNs in the z > 1.4 sample are undetected in the deep X-ray data but exhibit power-law SEDs longward of ~2 μm (rest frame) indicative of obscured AGNs. The results of our survey indicate that rest-frame UV selection and spectroscopy presently constitute the most timewise efficient method of culling large samples of high-redshift galaxies with a wide range in intrinsic properties, and the data presented here will add significantly to the multiwavelength legacy of GOODS.
No takes yet. Share an insight, caveat, or question.
Reddy et al. (2006) studied this question.
Synapse has enriched 10 related papers. Consider them for comparative context: