Colors of Ellipticals from GALEX to Spitzer
  Multi-color photometry is presented for a large sample of local ellipticals
selected by morphology and isolation. The sample uses data from GALEX, SDSS,
2MASS and Spitzer to cover the filters NUV, ugri, JHK and 3.6mum. Various
two-color diagrams, using the half-light aperture defined in the 2MASS J
filter, are very coherent from color to color, meaning that galaxies defined to
be red in one color are always red in other colors. Comparison to globular
cluster colors demonstrates that ellipticals are *not* composed of a single
age, single metallicity (e.g., [Fe/H]) stellar population, but require a
multi-metallicity model using a chemical enrichment scenario. Such a model is
sufficient to explain two-color diagrams and the color-magnitude relations for
all colors using only metallicity as a variable on a solely 12 Gyrs stellar
population with no evidence of stars younger than 10 Gyrs. The [Fe/H] values
that match galaxy colors range from -0.5 to +0.4, much higher (and older) than
population characteristics deduced from Lick/IDS line-strength system studies,
indicating an inconsistency between galaxy colors and line indices values for
reasons unknown. The NUV colors have unusual behavior signaling the rise and
fall of the UV upturn with elliptical luminosity. Models with BHB tracks can
reproduce this behavior indicating the UV upturn is strictly a metallicity
effect.
