SiO Masers in the Galactic Bulge and Disk: Kinematics from the BAaDE
  Survey
  We present the first results from the BAaDE (Bulge Asymmetries and Dynamic
Evolution) survey. Though only a subset of the complete survey ($\sim$2700 out
of $\sim$20000 final sources), our data comprise the largest radio kinematic
survey to date of stellar SiO masers observed toward the Galactic bulge and
plane from $-15^\circ < l < +12^\circ$ and $-6^\circ < b < +6^\circ$. Our
sources include a substantial number of line-of-sight (LoS) velocities in high
extinction regions within $\pm 1^\circ$ of the Galactic plane. When matched
with 2MASS photometry, our radio-detected sample lies significantly brighter
than and red-ward of the first red giant branch tip, reaching extremes of
$(J-Ks)_0 > 8$, colors consistent with Mira variables and mass losing AGB
stars. We see a clean division into two kinematic populations: a kinematically
cold ($\sigma \sim 50\rm\ km\ sec^{-1}$) population that we propose is in the
foreground disk, consisting of giants with 2MASS $Ks<5.5$, and a kinematically
hot ($\sigma \sim 100\rm\ km\ sec^{-1}$) candidate bulge/bar population for
most giants with $Ks>5.5$. Only the kinematically hot giants with $Ks>5.5$
include the reddest stars. Adopting 8.3 kpc to the Galactic Center, and
correcting for foreground extinction, we find that most of the sources have
$M_{bol} \sim -5$, consistent with their being luminous, and possibly
intermediate age, AGB stars. We note some tension between the possibly
intermediate age of the kinematically hot population, and its high velocity
dispersion compared to the disk.
