Galaxy Zoo: Quantitative Visual Morphological Classifications for 48,000
  galaxies from CANDELS
  We present quantified visual morphologies of approximately 48,000 galaxies
observed in three Hubble Space Telescope legacy fields by the Cosmic And
Near-infrared Deep Extragalactic Legacy Survey (CANDELS) and classified by
participants in the Galaxy Zoo project. 90% of galaxies have z < 3 and are
observed in rest-frame optical wavelengths by CANDELS. Each galaxy received an
average of 40 independent classifications, which we combine into detailed
morphological information on galaxy features such as clumpiness, bar
instabilities, spiral structure, and merger and tidal signatures. We apply a
consensus-based classifier weighting method that preserves classifier
independence while effectively down-weighting significantly outlying
classifications. After analysing the effect of varying image depth on reported
classifications, we also provide depth-corrected classifications which both
preserve the information in the deepest observations and also enable the use of
classifications at comparable depths across the full survey. Comparing the
Galaxy Zoo classifications to previous classifications of the same galaxies
shows very good agreement; for some applications the high number of independent
classifications provided by Galaxy Zoo provides an advantage in selecting
galaxies with a particular morphological profile, while in others the
combination of Galaxy Zoo with other classifications is a more promising
approach than using any one method alone. We combine the Galaxy Zoo
classifications of "smooth" galaxies with parametric morphologies to select a
sample of featureless disks at 1 < z < 3, which may represent a dynamically
warmer progenitor population to the settled disk galaxies seen at later epochs.
