Dr Sam Lindsay

Assistant Editor (MNRAS), Royal Astronomical Society

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Faint Images in the Radio Sky at Twenty-cm (FIRST)

FIRST is a 1.4 GHz survey using the VLA in B configuration to cover ~10,000 square degrees of the northern sky to a 5σ detection limit of 1 mJy. While covering a smaller area, and having a smaller instantaneous field of view than the NRAO VLA Sky Survey (NVSS), it is slightly deeper and with a far superior 5.4 arcsec resolution is able to resolve individual radio lobes/jets associated with active galactic nuclei (AGN). The radio sky above 1 mJy is dominated by AGN with a median redshift z~1, so the ~1,000,000 source catalogue of FIRST is an extremely useful data set for a range of science goals.

References: Becker et al. (1995)

Image from Baldry et al. 2010

Galaxy And Mass Assembly (GAMA)

GAMA is a redshift survey using the 3.9m Anglo-Australian Telescope (AAT) to cover three equatorial 12x4 degree fields (9h, 12h and 14h30) to a depth of r<19.8. The AAOmega spectrograph provides ~4-5 Å resolution spectra between 3720 and 8850 Å for around 140,000 galaxies up to z~0.6. At the peak redshift of 0.2, GAMA is able to fully sample structure scales of several hundred Mpc.


References: Driver et al. (2011), Hopkins et al. (2013)

Image from Jarvis et al. 2013

VISTA Deep Extragalactic Observations (VIDEO)

VIDEO is a ~12 square degree survey in the near-infrared (ZYJHK) designed to probe the evolution of galaxies and large-scale structures out to z=4, as well as higher redshift AGN. 5σ AB-magnitude depths are 25.7/24.5/24.4/24.1/23.8 in Z/Y/J/H/K, respectively. Overlap with deep optical fields such as CFHTLS-D1 allow for significant improvement on photometric redshifts, particularly at 1<z<4 with the added sensitivity to the Balmer and 4000 Å breaks in the near-infrared.

References: Bonfield et al. (2010), Jarvis et al. (2013)


Cosmological Evolution Survey (COSMOS)

COSMOS is an astronomical survey designed to probe the formation and evolution of galaxies as a function of cosmic time (redshift) and large scale structure environment. The survey covers a 2 square degree equatorial field with imaging by most of the major space-based telescopes (Hubble, Spitzer, GALEX, XMM, Chandra) and a number of large ground based telescopes (Subaru, VLA, ESO-VLT, UKIRT, NOAO, CFHT and others). Over 2 million galaxies are detected, spanning 75% of the age of the universe. 

The deep radio component of the survey, using the VLA, goes to a 5σ flux limit of ~75 μJy at 1.4 GHz with ~1.5" resolution, yielding ~3,600 radio sources.

References: Scoville et al. (2007), Schinnerer et al. (2007)