Andrea Kunder, Andreas Koch, R. Michael Rich, Roberto de Propris, Christian D. Howard, Scott A. Stubbs, Christian I. Johnson, Juntai Shen, Yougang Wang, Annie C. Robin, John Kormendy, Mario Soto, Peter Frinchaboy, David B. Reitzel, HongSheng Zhao, Livia Origlia
We present new radial velocity measurements from the Bulge Radial Velocity
Assay (BRAVA), a large scale spectroscopic survey of M-type giants in the
Galactic bulge/bar region. The sample of ~4500 new radial velocities, mostly in
the region -10 deg < l < +10 deg and b ~ -6 deg more than doubles the existent
published data set. Our new data extend our rotation curve and velocity
dispersion profile to +20 deg, which is ~2.8 kpc from the Galactic Center. The
new data confirm the cylindrical rotation observed at -6 deg and -8 deg, and
are an excellent fit to the Shen et al. (2010) N-body bar model. We measure the
strength of the TiO molecular band as a first step towards a metallicity
ranking of the stellar sample, from which we confirm the presence of a vertical
abundance gradient. Our survey finds no strong evidence of previously unknown
kinematic streams. We also publish our complete catalog of radial velocities,
photometry, TiO band strengths, and spectra, which is available at the IRSA
archive: http://irsa.ipac.caltech.edu/ as well as at UCLA:
http://brava.astro.ucla.edu/.
View original:
http://arxiv.org/abs/1112.1955
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