The definitive version can be found at: http://www.wiley.com/ Copyright Wiley BlackwellWe use new mid-infrared (mid-IR) photometry from the Spitzer Space Telescope to study the relations between low-frequency radio luminosity density L-nu 151 (MHz), mid-IR (12 mu m rest frame) luminosity nu L-nu 12 (mu m) and optical emission-line ([O II]) luminosity L-[O II], for a complete sample of z similar to 1 radio galaxies from the 3CRR, 6CE, 6C*, 7CRS and TOOT00 surveys. The narrow redshift span of our sample (0.9 < z < 1.1) means that it is unbiased to evolutionary effects. We find evidence that these three quantities are positively correlated. The scaling between nu L-nu 12 (mu m) and L-[O II] is similar to that seen in other active galactic nuclei samples, consistent with both nu L-nu 12 (mu m) and L-[O II] tracing accretion rate. We show that the positive correlation between nu L-nu 12 (mu m) and L-nu 151 (MHz) implies that there is a genuine lack of objects with low values of nu L-nu 12 (mu m) at high values of L-nu 151 (MHz). Given that nu L-nu 12 (mu m) traces accretion rate, while L-nu 151 (MHz) traces jet power, this can be understood in terms of a minimum accretion rate being necessary to produce a given jet power. This implies that there is a maximum efficiency with which accreted energy can be chanelled into jet power and this efficiency is of the order of unity

The Southern Photometric Local Universe Survey (S-PLUS) is imaging ∼9300 deg2 of the celestial sphere in 12 optical bands using a dedicated 0.8 m robotic telescope, the T80-South, at the Cerro Tololo Inter-american Observatory, Chile. The telescope is equipped with a 9.2k × 9.2k e2v detector with 10 $\rm {\mu m}$ pixels, resulting in a field of view of 2 deg2 with a plate scale of 0.55 arcsec pixel−1. The survey consists of four main subfields, which include two non-contiguous fields at high Galactic latitudes (|b| > 30°, 8000 deg2) and two areas of the Galactic Disc and Bulge (for an additional 1300 deg2). S-PLUS uses the Javalambre 12-band magnitude system, which includes the 5 ugriz broad-band filters and 7 narrow-band filters centred on prominent stellar spectral features: the Balmer jump/[OII], Ca H + K, H δ, G band, Mg b triplet, H α, and the Ca triplet. S-PLUS delivers accurate photometric redshifts (δz/(1 + z) = 0.02 or better) for galaxies with r < 19.7 AB mag and z < 0.4, thus producing a 3D map of the local Universe over a volume of more than $1\, (\mathrm{Gpc}/h)^3$. The final S-PLUS catalogue will also enable the study of star formation and stellar populations in and around the Milky Way and nearby galaxies, as well as searches for quasars, variable sources, and low-metallicity stars. In this paper we introduce the main characteristics of the survey, illustrated with science verification data highlighting the unique capabilities of S-PLUS. We also present the first public data release of ∼336 deg2 of the Stripe 82 area, in 12 bands, to a limiting magnitude of r = 21, available at datalab.noao.edu/splus.

Gamma‐ray bursts (GRBs) are powerful probes of the early Universe, but locating and identifying very distant GRBs remain challenging. We report here the discovery of the K‐band afterglow of Swift GRB 060923A, imaged within the first hour post‐burst, and the faintest so far found. It was not detected in any bluer bands to deep limits, making it a candidate very high‐z burst (z≳ 11). However, our later‐time optical imaging and spectroscopy reveal a faint galaxy coincident with the GRB position which, if it is the host, implies a more moderate redshift (most likely z≲ 2.8) and therefore that dust is the likely cause of the very red‐afterglow colour. This being the case, it is one of the few instances so far found of a GRB afterglow with high‐dust extinction.

Understanding the evolution of accretion activity is fundamental to our understanding of how galaxies form and evolve over the history of the Universe. We analyse a complete sample of 27 radio galaxies which includes both high-excitation (HEGs) and low excitation galaxies (LEGs), spanning a narrow redshift range of 0.9 < z < 1.1 and covering a factor of ∼ 1000 in radio luminosity. Using data from the Spitzer Space Telescope combined with ground-based optical and near-infrared imaging, we show that the host galaxies have masses in the range of 10.7 < log 10 (M/M ⊙ ) < 12.0 with HEGs and LEGs exhibiting no difference in their mass distributions. We also find that HEGs accrete at significantly higher rates than LEGs, with the HEG/LEG division lying at an Eddington ratio of λ ∼ 0.04, which is in excellent agreement with theoretical predictions of where the accretion rate becomes radiatively inefficient, thus supporting the idea of HEGs and LEGs being powered by different modes of accretion. Our study also shows that at least up to L 151MHz ∼ 3 × 10 27 W Hz −1 sr −1 , HEGs and LEGs are indistinguishable in terms of their radio properties. From this result we infer that, at least for the lower radio luminosity range, another factor besides accretion rate must play an important role in the process of triggering jet activity.