A new model for the Milky Way bar

We use Schwarzschild's orbit-superposition technique to construct self-consistent models of the Galactic bar. Using χ ² minimization, we find that the best-fitting Galactic bar model has a pattern speed Ω _p = 60kms ^-1kpc ^-1, disc mass M _d = 1.0 × 10 ¹¹M _⊙ and bar angle θ _bar = 20° for an adopted bar mass M _bar = 2 × 10 ¹⁰M _⊙. The model can reproduce not only the three-dimensional and projected density distributions but also velocity and velocity dispersion data from the Bulge Radial Velocity Assay (BRAVA) survey. We also predict the proper motions in the range l = [-12°, 12°], b = [-10°, 10°], which appear to be higher than observations in the longitudinal direction. The model is stable within a time-scale of 0.5 Gyr, but appears to deviate from steady state on longer time-scales. Our model can be further tested by future observations such as those from GAIA.