Ultraviolet Imaging of the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey Fields (UVCANDELS)

UVCANDELS offers wide-area extragalactic UV imaging of four of the premier HST deep-wide survey fields defined by CANDELS. The program is motivated by an investigation of galaxy evolution during the epoch of vigorous star formation at 0.5 < z < 3 by: (1) using the high spatial resolution UV and Blue data (700 pc at z~1) to study the structural evolution of galaxies and create 2D maps of their star-formation history, (2) combining UVCANDELS with Herschel legacy data to trace the evolution of the dust content of moderate redshift (z < 1) galaxies, (3) probing the role of environment in the evolution of low-mass star-forming galaxies, (4) investigating the decay of star-formation in massive early-type galaxies and the role of minor mergers, (5) constraining the escape fraction of ionizing radiation from galaxies at z ~ 2.5 to better understand how star-forming galaxies reionized the Universe at z > 6. UVCANDELS consists of WFC3/F275W imaging of four CANDELS fields (~430 sq. arcmin combined), reaching AB=27 for compact galaxies (SFR~0.2 Msun/yr at z=1), together with parallel ACS/F435W (AB>=28.0) imaging. For each field (GOODS-N, GOODS-S, COSMOS and EGS), we deliver image mosaics of the new F275W observations. The mosaics are made on both 60mas and 30mas pixel grids. The astrometry is aligned to the CANDELS optical 30mas mosaics (F814W for COSMOS and F606W for the rest), with a small relative offset (usually <0.15 pixel [<45 mas]). We also deliver new ACS/F435W images for the COSMOS and EGS Fields over the same area. The F275W area of the GOODS fields falls within the original GOODS F435W coverage.