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
CANDELS Areas and 5σ Limiting Magnitudes
[668 sq. arcmin]
[120 sq. arcmin]
Detailed field maps are available on the Field Maps page.