The X-Shaped Milky Way Bulge in OGLE-III Photometry and in N-Body Models
  We model the split red clump of the Galactic bulge in OGLE-III photometry,
and compare the results to predictions from two N-body models. Our analysis
yields precise maps of the brightness of the two red clumps, the fraction of
stars in the more distant peak, and their combined surface density. We compare
the observations to predictions from two N-body models previously used in the
literature. Both models correctly predict several features as long as one
assumes an angle $\alpha_{\rm{Bar}} \approx 30^{\circ}$ between the Galactic
bar's major axis and the line of sight to the Galactic centre. In particular
that the fraction of stars in the faint red clump should decrease with
increasing longitude. The biggest discrepancies between models and data are in
the rate of decline of the combined surface density of red clump stars toward
negative longitudes and of the brightness difference between the two red clumps
toward positive longitudes, with neither discrepancy exceeding $\sim$25% in
amplitude. Our analysis of the red giant luminosity function also yields an
estimate of the red giant branch bump parameters toward these high-latitude
fields, and evidence for a high rate ($\sim$25%) of disk contamination in the
bulge at the colour and magnitude of the red clump, with the disk contamination
rate increasing toward sightlines further distant from the plane.
