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A correction to the article "The Impact of Bars on Disk Breaks as Probed by S4G Imaging" published in the February 2016 issue is presented.

Using 3.6 and 4.5 μm images of 73 late-type, edge-on galaxies from the S4G survey, we compare the richness of the globular cluster populations of these galaxies to those of early-type galaxies that we measured previously. In general, the galaxies presented here fill in the distribution for galaxies with lower stellar mass, M*, specifically , overlap the results for early-type galaxies of similar masses, and, by doing so, strengthen the case for a dependence of the number of globular clusters per 109M⊙ of galaxy stellar mass, TN, on M*. For we find the relationship can be satisfactorily described as when M* is expressed in solar masses. The functional form of the relationship is only weakly constrained, and extrapolation outside this range is not advised. Our late-type galaxies, in contrast to our early types, do not show the tendency for low-mass galaxies to split into two TN families. Using these results and a galaxy stellar mass function from the literature, we calculate that, in a volume-limited, local universe sample, clusters are most likely to be found around fairly massive galaxies (M* ∼ 1010.8M⊙) and present a fitting function for the volume number density of clusters as a function of parent-galaxy stellar mass. We find no correlation between TN and large-scale environment, but we do find a tendency for galaxies of fixed M* to have larger TN if they have converted a larger proportion of their baryons into stars. [ABSTRACT FROM AUTHOR]

One of the most challenging aspects of studying galaxies in the universe is the infrequent confirmation of their redshifts through spectroscopy, a phenomenon thought to occur from the increasing opacity of the intergalactic medium to Lyα photons at . The resulting redshift uncertainties inhibit the efficient search for [C ii] in galaxies with sub-millimeter instruments such as ALMA, given their limited scan speed for faint lines. One means by which to improve the precision of the inferred redshifts is to exploit the potential impact of strong nebular emission lines on the colors of z ∼ 4 – 8 galaxies as observed by Spitzer/IRAC. At , galaxies exhibit IRAC colors as blue as , likely due to the contribution of [O iii]+Hβ to the 3.6 μm flux combined with the absence of line contamination in the 4.5 μm band. In this paper we explore the use of extremely blue colors to identify galaxies in the narrow redshift window 6.6 – 6.9. When combined with an I-dropout criterion, we demonstrate that we can plausibly select a relatively clean sample of galaxies. Through a systematic application of this selection technique to our catalogs from all five CANDELS fields, we identify 20 probable 6.6 – 6.9 galaxies. We estimate that our criteria select the ∼50% strongest line emitters at and from the IRAC colors we estimate a typical [O iii] rest-frame equivalent width of 1085 Å for this sample. The small redshift uncertainties on our sample make it particularly well suited for follow-up studies with facilities such as ALMA. [ABSTRACT FROM AUTHOR]