Reconstructing the Near-IR Background Fluctuations from known Galaxy
  Populations using Multiband Measurements of Luminosity Functions
  We model fluctuations in the Cosmic Infrared Background (CIB) arising from
known galaxy populations using 233 measured UV, optical and NIR luminosity
functions (LF) from a variety of surveys spanning a wide range of redshifts. We
compare best-fit Schechter parameters across the literature and find clear
indication of evolution with redshift. Providing fitting formulae for the
multi-band evolution of the LFs out to z~5, we calculate the total emission
redshifted into the near-IR bands in the observer frame and recover the
observed optical and near-IR galaxy counts to a good accuracy. Our empirical
approach, in conjunction with a halo model describing the clustering of
galaxies, allows us to compute the fluctuations of the unresolved CIB and
compare the models to current measurements. We find that fluctuations from
known galaxy populations are unable to account for the large scale CIB
clustering signal seen by Spitzer/IRAC and AKARI/IRC and continue to diverge
out to larger angular scales. This holds true even if the LFs are extrapolated
out to faint magnitudes with a steep faint-end slope all the way to z=8. We
also show that removing resolved sources to progressively fainter magnitude
limits, isolates CIB fluctuations to increasingly higher redshifts. Our
empirical approach suggests that known galaxy populations are not responsible
for the bulk of the fluctuation signal seen in the measurements and favors a
very faint population of highly clustered sources.
