TY - JOUR
T1 - Deep 3-GHz observations of the Lockman Hole North with the Very Large Array - II. Catalogue and µJy source properties
AU - Vernstrom, T.
AU - Scott, Douglas
AU - Wall, J. V.
AU - Condon, J. J.
AU - Cotton, W. D.
AU - Kellermann, K. I.
AU - Perley, R. A.
PY - 2016/11/1
Y1 - 2016/11/1
N2 - 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 (VLA). We describe the reduction and cataloguing process, which yielded an image with 8 arcsec resolution and instrumental noise of sigma(n) = 1.01 mu Jy beam(-1) rms (before primary-beam corrections) and a catalogue of 558 sources detected above 5 sigma(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 X-ray, optical, infrared, radio, and redshift catalogues are also presented. The X-ray, optical and infrared data, as well as active galactic nuclei (AGN) selection criteria allow us to classify 10 per cent as radio-loud AGN, 28 per cent as radio-quiet AGN, and 58 per cent as star-forming galaxies, with only 4 per cent unclassified.
AB - 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 (VLA). We describe the reduction and cataloguing process, which yielded an image with 8 arcsec resolution and instrumental noise of sigma(n) = 1.01 mu Jy beam(-1) rms (before primary-beam corrections) and a catalogue of 558 sources detected above 5 sigma(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 X-ray, optical, infrared, radio, and redshift catalogues are also presented. The X-ray, optical and infrared data, as well as active galactic nuclei (AGN) selection criteria allow us to classify 10 per cent as radio-loud AGN, 28 per cent as radio-quiet AGN, and 58 per cent as star-forming galaxies, with only 4 per cent unclassified.
KW - methods: data analysis
KW - surveys
KW - cosmology: observations
KW - radio continuum: galaxies
KW - ACTIVE GALACTIC NUCLEI
KW - RADIO-SOURCE POPULATION
KW - STAR-FORMATION HISTORY
KW - FIELD-SOUTH REGION
KW - EXTRAGALACTIC SURVEY
KW - OPTICAL IDENTIFICATIONS
KW - SPECTROSCOPIC CATALOG
KW - LUMINOSITY FUNCTIONS
KW - SOURCE EXTRACTION
KW - HIGH-REDSHIFT
U2 - 10.1093/mnras/stw1836
DO - 10.1093/mnras/stw1836
M3 - Article
SN - 0035-8711
VL - 462
SP - 2934
EP - 2949
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
IS - 3
ER -