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Survey Description

The Cosmic Assembly Near-IR Deep Extragalactic Legacy Survey (CANDELS; Grogin et al. 2011; Koekemoer et al. 2011) is designed to document the first third of galactic evolution from z = 8 to 1.5 via deep imaging of more than 250,000 galaxies with WFC3/IR and ACS. It will also find the first Type Ia SNe beyond z > 1.5 and establish their accuracy as standard candles for cosmology. Five premier multi-wavelength sky regions are selected; each has multi-wavelenght data from Spitzer and other facilities, and has extensive spectroscopy of the brighter galaxies. The use of five widely separated fields mitigates cosmic variance and yields statistically robust and complete samples of galaxies down to 109 solar masses out to z ~ 8.

The program merges two originally separate MCT proposals. The Faber program incorporates a “Wide” imaging survey in three separate fields to ~ 2 orbit depth over ~ 0.2 sq. degrees, plus a “Deep” imaging survey to ~ 12 orbit depth in the two GOODS regions over ~ 0.04 sq. degrees. In combination with ultra-deep imaging from the Hubble Ultradeep Field program (GO 11563), the result is a three-tiered strategy that efficiently samples both bright/rare and faint/common extragalactic objects. The Ferguson program adds an extensive high-redshift Type Ia SNe search, plus ultraviolet "daytime" UVIS exposures in GOODS-N to exploit the CVZ opportunity in that field.

Draft versions of the CANDELS Overview Paper and Data Paper are available as a resource for astronomers preparing HST Cycle 19 proposals. [Download Overview Paper (23 Mb)] [Download Data Paper (86 Mb)] -- 2/17/2011

Survey Summary

CANDELS Areas and 5σ Limiting Magnitudes

  Wide Program
[668 sq. arcmin]
Deep Program
[120 sq. arcmin]
Filters Sensitivity1 Sensitivity1
-- 27.82
-- 27.62
ACS/WFC F435W 27.83 27.8
ACS/WFC F606W 27.6 28.2
ACS/WFC F775W 27.53 27.5
ACS/WFC F814W 27.5 28.4
ACS/WFC F850LP 27.33 27.3
WFC3/IR F105W 26.6 27.3
WFC3/IR F125W 26.4 27.4
WFC3/IR F160W 26.5 27.2

1 Limiting magnitudes correspond to 5x the photometric error within a 0.25"-radius aperture.
2 Available only in CANDELS GOODS-N.
3 Available only in the Deep flanking fields.

Field Maps

Detailed field maps are available on the Field Maps page.