Modeling the angular correlation function and its full covariance in
  Photometric Galaxy Surveys
  Near future cosmology will see the advent of wide area photometric galaxy
surveys, like the Dark Energy Survey (DES), that extent to high redshifts (z ~
1 - 2) but with poor radial distance resolution. In such cases splitting the
data into redshift bins and using the angular correlation function $w(\theta)$,
or the $C_{\ell}$ power spectrum, will become the standard approach to extract
cosmological information or to study the nature of dark energy through the
Baryon Acoustic Oscillations (BAO) probe. In this work we present a detailed
model for $w(\theta)$ at large scales as a function of redshift and bin width,
including all relevant effects, namely nonlinear gravitational clustering,
bias, redshift space distortions and photo-z uncertainties. We also present a
model for the full covariance matrix characterizing the angular correlation
measurements, that takes into account the same effects as for $w(\theta)$ and
also the possibility of a shot-noise component and partial sky coverage.
Provided with a large volume N-body simulation from the MICE collaboration we
built several ensembles of mock redshift bins with a sky coverage and depth
typical of forthcoming photometric surveys. The model for the angular
correlation and the one for the covariance matrix agree remarkably well with
the mock measurements in all configurations. The prospects for a full shape
analysis of $w(\theta)$ at BAO scales in forthcoming photometric surveys such
as DES are thus very encouraging.
