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arXiv · 1112.1955

The Bulge Radial Velocity Assay (BRAVA): II. Complete Sample and Data Release

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
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Abstract

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/.

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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. 2011-12-08. The Bulge Radial Velocity Assay (BRAVA): II. Complete Sample and Data Release. https://doi.org/10.1088/0004-6256%2F143%2F3%2F57

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