Colors of Dwarf Ellipticals from GALEX to WISE
  Multi-color photometry is presented for a sample of 60 dwarf ellipticals (dE)
selected by morphology. The sample uses data from GALEX, SDSS and WISE to
investigate the colors in filters NUV, ugri and W1 (3.4mum). We confirm the
blueward shift in the color-magnitude relation for dwarf ellipticals, compared
to CMR for bright ellipticals, as seen in previous studies. However, we find
the deviation in color across the UV to near-IR for dE's is a strong signal of
a younger age for dwarf ellipticals, one that indicates decreasing mean age
with lower stellar mass. Lower mass dE's are found to have mean ages of 4 Gyrs
and mean [Fe/H] values of -1.2. Age and metallicity increase to the most
massive dE's with mean ages similar to normal ellipticals (12 Gyrs) and their
lowest metallicities ([Fe/H] = -0.3). Deduced initial star formation rates for
dE's, combined with their current metallicities and central stellar densities,
suggests a connection between field LSB dwarfs and cluster dE's, where the
cluster environment halts star formation for dE's triggering a separate
evolutionary path.
