Evidence of a metal-rich Galactic bar from the vertex deviation of the velocity ellipsoid

YWe combine radial velocities, proper motions, and low- resolution abundances for a sample of 315 K and M giants in the Baade's window ( l, b) p ( 0.9 degrees, - 4 degrees) Galactic bulge field. The velocity ellipsoid of stars with dex shows a vertex deviation in the plot of radial versus transverse velocity, consistent with that [ Fe/ H] 1 - 0.5 expected from a population with orbits supporting a bar. We demonstrate that the significance of this vertex deviation, using nonparametric rank correlation statistic, is 199%. The velocity ellipsoid for the metal- poor ([FeH] < - 0.5) part of the population shows no vertex deviation and is consistent with an isotropic, oblate rotating population. We find no evidence of kinematic subgroups, but there is a mild tendency for the vertical velocity dispersion sigma(b) to decrease with increasing metallicity.