The Host Galaxies of Micro-Jansky Radio Sources

Luchsinger, Kristen M.; Lacy, Mark; Jones, Kristen M.; Mauduit, Jean‐Christophe; Pforr, Janine; Surace, J.; Vaccari, M.; Farrah, D.; Gonzales-Solares, E.; Jarvis, Matt J.; Maraston, Claudia; Marchetti, L.; Oliver, Seb; Afonso, J.; Cappozi, D.; Sajina, Anna

doi:10.1088/0004-6256/150/3/87

Cited by 16 publications

(12 citation statements)

References 68 publications

(80 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Our catalogue has 184 spectroscopic matches with z spec = 0.6 and 456 photometric redshifts with z phot = 0.9. These values are similar to those found byLuchsinger et al (2015), who examined cross-matched radio and optical sources in the Lockman Hole East and found a peak in the distribution near z = 0.7, with a median redshift of z = 1.04. Panel (b) ofFig.…”

supporting

confidence: 89%

Deep 3-GHz observations of the Lockman Hole North with the Very Large Array – II. Catalogue and μJy source properties

Vernstrom

Scott

Wall

et al. 2016

Mon. Not. R. Astron. Soc.

View full text Add to dashboard Cite

This is the second of two papers describing the observations and source catalogues derived from sensitive 3-GHz images of the Lockman Hole North using the Karl G. Jansky Very Large Array. We describe the reduction and cataloguing process, which yielded an image with 8 arcsec resolution and instrumental noise of σ n = 1.01 µJy beam −1 rms (before primary beam corrections) and a catalogue of 558 sources detected above 5σ n . We include details of how we estimate source spectral indices across the 2-GHz VLA bandwidth, finding a median index of −0.76 ± 0.04. Stacking of source spectra reveals a flattening of spectral index with decreasing flux density. We present a source count derived from the catalogue. We show a traditional count estimate compared with a completely independent estimate made via a P(D) confusion analysis, and find very good agreement. Cross-matches of the catalogue with Xray, optical, infrared, radio, and redshift catalogues are also presented. The X-ray, optical and infrared data, as well as AGN selection criteria allow us to classify 10 per cent as radio-loud AGN, 28 percent as radio-quiet AGN, and 58 per cent as star-forming galaxies, with only 4 per cent unclassified.

show abstract

supporting

confidence: 89%

Deep 3-GHz observations of the Lockman Hole North with the Very Large Array – II. Catalogue and μJy source properties

Vernstrom

Scott

Wall

et al. 2016

Mon. Not. R. Astron. Soc.

View full text Add to dashboard Cite

show abstract

“…However, this flattening is not seen in the deep 10C count so it is not clear what contribution, if any, star-forming galaxies make to the source population at S 15.7 > 0.1 mJy. This is consistent with several recent studies of the faint (S 1.4 GHz < 0.1 mJy) source population at lower frequencies [23,14,16], which also find fewer star-forming galaxies than predicted by the simulation.…”

Section: Pos(extra-radsur2015)026supporting

confidence: 93%

Exploring the faint source population at 15.7 GHz

Whittam¹

2016

Proceedings of the Many Facets of Extragalactic Radio Surveys: Towards New Scientific Challenges — PoS(EXTRA-RADSUR2015)

View full text Add to dashboard Cite

We discuss our current understanding of the nature of the faint, high-frequency radio sky. The Tenth Cambridge (10C) survey at 15.7 GHz is the deepest high-frequency radio survey to date, covering 12 square degrees to a completeness limit of 0.5 mJy, making it the ideal starting point from which to study this population. In this work we have matched the 10C survey to several lower-frequency radio catalogues and a wide range of multi-wavelength data (near-and farinfrared, optical and X-ray). We find a significant increase in the proportion of flat-spectrum sources at flux densities below 1 mJy -the median radio spectral index between 15.7 GHz and 610 MHz changes from 0.75 for flux densities greater than 1.5 mJy to 0.08 for flux densities less than 0.8 mJy. The multi-wavelength analysis shows that the vast majority (> 94 percent) of the 10C sources are radio galaxies; it is therefore likely that these faint, flat spectrum sources are a result of the cores of radio galaxies becoming dominant at high frequencies.We have used new observations to extend this study to even fainter flux densities, calculating the 15.7-GHz radio source count down to 0.1 mJy, a factor of five deeper than previous studies. There is no evidence for a new population of sources, showing that the high-frequency sky continues to be dominated by radio galaxies down to at least 0.1 mJy.

show abstract

“…Sources not detected at 24 µm, and characterized by 24 µm to 1.4 GHz flux density ratio upper limits not stringent enough for a reliable classification, were classified based on their red IRAC colors (i.e. their 8.0 to 4.5 µm and 5.8 to 3.6 flux density ratios; see Luchsinger et al 2015 for more details). In the recent literature RQ AGNs in deep radio-selected samples are separated from SFGs based on their IRAC colors and, when available, X-ray luminosities (see e.g.…”

Section: Constraints From Wide-area Source Countsmentioning

confidence: 99%

The Lockman Hole Project: new constraints on the sub-mJy source counts from a wide-area 1.4 GHz mosaic

Prandoni

Guglielmino

Morganti

et al. 2018

Monthly Notices of the Royal Astronomical Society

117

View full text Add to dashboard Cite

This paper is part of a series discussing the results obtained in the framework of a wide international collaboration -the Lockman Hole Project -aimed at improving the extensive multi-band coverage available in the Lockman Hole region, through novel deep, wide-area, multi-frequency (60, 150, 350 MHz and 1.4 GHz) radio surveys. This multi-frequency, multiband information will be exploited to get a comprehensive view of star formation and AGN activities in the high redshift Universe from a radio perspective. In this paper we present novel 1.4 GHz mosaic observations obtained with the Westerbork Synthesis Radio Telescope (WSRT). With an area coverage of 6.6 square degrees, this is the largest survey reaching an rms noise of 11 µJy/b. In this paper we present the source catalogue (∼ 6000 sources with flux densities S > ∼ 55 µJy (5σ), and we discuss the 1.4 GHz source counts derived from it. Our source counts provide very robust statistics in the flux range 0.1 < S < 1 mJy, and are in excellent agreement with other robust determinations obtained at lower and higher flux densities. A clear excess is found with respect to the counts predicted by the semi-empirical radio sky simulations developed in the framework of the SKA Simulated Skies project. A preliminary analysis of the identified (and classified) sources suggests this excess is to be ascribed to star forming galaxies, which seem to show a steeper evolution than predicted.

show abstract

The Host Galaxies of Micro-Jansky Radio Sources

Cited by 16 publications

References 68 publications

Deep 3-GHz observations of the Lockman Hole North with the Very Large Array – II. Catalogue and μJy source properties

Deep 3-GHz observations of the Lockman Hole North with the Very Large Array – II. Catalogue and μJy source properties

Exploring the faint source population at 15.7 GHz

The Lockman Hole Project: new constraints on the sub-mJy source counts from a wide-area 1.4 GHz mosaic

Contact Info

Product

Resources

About