VLA-COSMOS Project

Scientific Objective/Abstract
VLA-COSMOS Team
VLA-COSMOS Pilot Project
VLA-COSMOS Large Project
Data Access
Related Links
Internal Access

Scientific Objective/Abstract

The VLA Large Project VLA-COSMOS is a state-of-the-art (1.7'' resolution), deep (1sigma ~ 7.5 uJy), wide-field imaging survey at 1.4 GHz of the COSMOS 2 square-degree deep field with the VLA. The Cosmic Evolution Survey (COSMOS) is a pan-chromatic (X-ray to mm) observational project to perform the definitive study of galaxy and super-massive black hole evolution in the crucial redshift range of z = 0.5 to 3, with particular attention to the influence of environment and large scale structure. Two cornerstones of COSMOS are the HST ACS imaging (HST Treasury project) and the unprecedented spectroscopy of ~100,000 sources. The areal coverage is large enough to avoid cosmic variance, and to delineate structure on the largest relevant scales (~100 Mpc comoving). The VLA observations represent a fundamental contribution to the COSMOS project, providing definitive answers to a number of key questions, including:

the secure identification of dust-obscured galaxies and their contribution to the cosmic star formation history,
the evolution of the FIR/radio correlation for star forming galaxies,
the evolution of low luminosity radio AGN to high z, as well as
setting the absolute astrometry for the COSMOS field.

VLA-COSMOS Team

Eva Schinnerer, MPIA (PI: VLA-COSMOS Project)
Vernesa Smolcic, MPIA
Chris Carilli, NRAO
Nick Scoville, CalTech
Frank Bertoldi, MPIfR
Andrew Blain, CalTech
Marco Bondi, IRA/CNR
Paolo Ciliegi, INAF
Chris Impey, UArizona
Anton Koekemoer, STScI
Olivier Le Fevre, Laboratoire d'Astrophysique
C. Megan Urry, Yale
Paolo Vettolani, INAF

VLA-COSMOS Pilot Project

Configuration	VLA A-array (Aug. '03)
Observing time	10 hr (total)
Frequency	1.4 GHz ( = L band, 20cm)
Bandwidth	75 MHz (Multi-channel continuum mode)
Pointings	7 (hexagonal pattern)
Area	~ 0.84 sqrdeg (Diameter ~ 1 degree)
Resolution	1.9" x 1.6"; PA -23 degrees
Sensitivity	25-100 uJy/beam (inner to outermost regions)
Nr. of sources	246 sources detected, ~ 20 clearly extended
Data Products	(a) flux calibrated image with absolute astrometry
	(b) (parametric) source catalog (position, fluxes, sizes)
Timeline	August '03: A-array observations finished
	August '04: delivery of data products to community (via COSMOS archive)

	Lay-out of the pointings of the VLA pilot project in the field of the COSMOS survey (indicated by broken line) onto a DSS image of the area. The cross marks the COSMOS field center. Each circle represents the primary beam of the VLA at 1.4GHz.
	The S/N map of the VLA COSMOS pilot field as constructed using AIPS. Brighter colors indicate lower S/N values.

Paper accepted (AJ) (abstract, astro-ph)

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VLA-COSMOS Large Project

Configuration	VLA A-array (Oct. '04 - Jan. '05)
	VLA C-array (May '05 - Aug. '05)
Observing time	240 hr (A) + 24 hr (C)
	~10 hr per pointing in A-array
Frequency	1.4 GHz ( = L band, 20cm)
Bandwidth	75 MHz (Multi-channel continuum mode)
Pointings	23 (hexagonal pattern)
Area	~ 2 sqrdeg (1.4 x 1.4 degrees)
Resolution	~ 1.9" x 1.6"
Sensitivity	~ 10 uJy/beam (for inner 1 sqrdeg)
Nr. of sources	about 4,700 sources expected
Data Products	(a) flux calibrated image with absolute astrometry
	(b) (parametric) source catalog (position, fluxes, sizes)
Timeline	March '05: A-array observations finished
	March '06: delivery of data products (A-array) to community

The planned lay-out for the 23 VLA pointings covering the full COSMOS field are overlaid onto an DSS image of the field. The COSMOS HST field is indicated by a box (broken line). The 7 pointings of the 10hr VLA Pilot Project are highlighted by thicker lines. The cross marks the field center.

Data Access

All data are accessible from the COSMOS archive at IPAC/IRSA.

Pilot Project Data Products: Images (SIN, TAN projection), catalog (paper)

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