  We present the results of deep, ground based U-band imaging with the Large
Binocular Telescope of the Cosmic Evolution Survey (COSMOS) field as part of
the near-UV imaging program, UVCANDELS. We utilize a seeing sorted stacking
method along with night-to-night relative transparency corrections to create
optimal depth and optimal resolution mosaics in the U-band, which are capable
of reaching point source magnitudes of AB 26.5 mag at 3 sigma. These ground
based mosaics bridge the wavelength gap between the HST WFC3 F27W and ACS F435W
images and are necessary to understand galaxy assembly in the last 9-10 Gyr. We
use the depth of these mosaics to search for the presence of U-band intragroup
light (IGrL) beyond the local Universe. Regardless of how groups are scaled and
stacked, we do not detect any U-band IGrL to unprecedented U-band depths of
29.1-29.6 mag/arcsec2, which corresponds to an IGrL fraction of less than 1% of
the total group light. This stringent upper limit suggests that IGrL does not
contribute significantly to the Extragalactic Background Light at short
wavelengths. Furthermore, the lack of UV IGrL observed in these stacks suggests
that the atomic gas observed in the intragroup medium (IGrM) is likely not
dense enough to trigger star formation on large scales. Future studies may
detect IGrL by creating similar stacks at longer wavelengths or by
pre-selecting groups which are older and/or more dynamically evolved similar to
past IGrL observations of compact groups and loose groups with signs of
gravitational interactions.
