Astrophys. J., 861, 75-75 (2018/July-1)
SiO masers in the Galactic bulge and disk: kinematics from the BAaDE survey.
TRAPP A.C., RICH R.M., MORRIS M.R., SJOUWERMAN L.O., PIHLSTROM Y.M., CLAUSSEN M. and STROH M.C.
Abstract (from CDS):
We present the first results from the Bulge Asymmetries and Dynamic Evolution (BAaDE) survey. Though only a subset of the complete survey (∼2700 out of ∼20,000 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° < l < +12° and -6° < b < +6°. Our sources include a substantial number of line-of-sight velocities in high extinction regions within ±1° of the Galactic plane. When matched with 2MASS4 photometry, our radio-detected sample lies significantly brighter than and redward 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 (σ ∼ 50 km s–1) population that we propose is in the foreground disk, consisting of giants with 2MASS Ks < 5.5, and a kinematically hot (σ ∼ 100 km s–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 Mbol ∼ -5, consistent with their being luminous and possibly intermediate-age AGB stars. We note some tension between the possible intermediate age of the kinematically hot population, and its high-velocity dispersion compared to the disk.
© 2018. The American Astronomical Society. All rights reserved.
Galaxy: bulge - Galaxy: kinematics and dynamics - stars: AGB and post-AGB
View the reference in ADS
To bookmark this query, right click on this link: simbad:2018ApJ...861...75T and select 'bookmark this link' or equivalent in the popup menu