Young galaxy candidates in the Hubble Frontier Fields. I. A2744 Academic Article uri icon

abstract

  • We report the discovery of 24 Lyman-break candidates at 7 lesssim z lesssim 10.5, in the Hubble Frontier Fields (HFF) imaging data of A2744 (z= 0.308), plus Spitzer/IRAC data and archival ACS data. The sample includes a triple image system with a photometric redshift of z sime 7.4. This high redshift is geometrically confirmed by our lens model corresponding to deflection angles that are 12% larger than the lower-redshift systems used to calibrate the lens model at z= 2.019. The majority of our high-redshift candidates are not expected to be multiply lensed given their locations in the image plane and the brightness of foreground galaxies, but are magnified by factors of~ 1.3-15, so that we are seeing further down the luminosity function than comparable deep-field imaging. It is apparent that the redshift distribution of these sources does not smoothly extend over the full redshift range …

publication date

  • October 15, 2014