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J/A+A/599/A12 [Fe/H] and kinematics of 26 Galactic bulge fields (Zoccali+, 2017)

The GIRAFFE Inner Bulge Survey (GIBS). III. Metallicity distributions and kinematics of 26 Galactic bulge fields. Zoccali, M., Vasquez, S., Gonzalez, O. A., Valenti, E., Rojas-Arriagada, A., Minniti, J., Rejkuba, M., Minniti, D., McWilliam, A., Babusiaux, C., Hill, V., Renzini, A. <Astron. Astrophys. 599, A12 (2017)> =2017A&A...599A..12Z (SIMBAD/NED BibCode)
ADC_Keywords: Milky Way ; Abundances ; Photometry ; Radial velocities Keywords: stars: abundances - Galaxy: bulge - Galaxy: structure - Galaxy: kinematics and dynamics - Galaxy: stellar content Abstract: Several recent studies have demonstrated that the Galactic bulge hosts two components with different mean metallicities, and possibly different spatial distribution and kinematics. As a consequence, both the metallicity distribution and the radial velocity of bulge stars vary across different line of sights. We present here the metallicity distribution function of red clump stars in 26 fields spread across a wide area of the bulge, with special emphasis on fields close to Galactic plane, at latitudes b=-2 and b=-1, that were not explored before. This work includes new metallicities from a sample of ∼5000 K giant stars, observed at spectral resolution R∼6500, in the Calcium II Triplet region. They are the main dataset of the GIRAFFE Inner Bulge Survey. As part of the same survey we have previously published results for a sample of ∼600 K giant stars, at latitude b~-4 derived from higher resolution spectra (R=22500). The combined sample allows us to trace and characterize the metal poor and metal rich bulge populations down to the inner bulge. We present a density map for each of the two components. Contrary to the expectations from previous works, we found the metal poor population to be more centrally concentrated than the metal rich one, and with a more axisymmetric spatial distribution. The metal rich population, on the other hand, is arranged in a boxy distribution, consistent with an edge-on bar. By coupling metallicities and radial velocities we show that the metal poor population has a velocity dispersion that varies rather mildly with latitude. On the contrary, the metal rich population has a low velocity dispersion far from the plane (b=-8.5) but it has a steeper gradient with latitude, becoming higher than the metal poor one in the innermost field (b=-1). This work provides new observational constraints on the actual chemodynamical properties of the Galactic bulge, that will help discriminating among different formation models. Description: In this table we provide coordinates, VVV magnitudes, radial velocities and metallicities for ∼5000 K giant stars observed at spectral resolution R∼6500, in the Calcium II Triplet region. Their metallicities were derived using a CaT calibration developed for this survey (Vasquez et al., 2015, Cat. J/A+A/555/A91). In addition, a set of ∼600 K giant stars, corresponding to the high resolution portion (R=22500) of the survey, and published in the paper II of this series (Gonzalez et al., 2015, Cat. J/A+A/584/A46), is included for completitude. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1.dat 86 5588 Coordinates, VVV magnitudes, radial velocities and metallicities of the program stars
See also: J/A+A/562/A66 : GIRAFFE Inner Bulge Survey (GIBS). I. (Zoccali+, 2014) J/A+A/584/A46 : GIRAFFE Inner Bulge Survey (GIBS). II. (Gonzalez+, 2015) J/A+A/580/A121 : Galactic bulge stars CaT/[Fe/H] calibration (Vasquez+, 2015) Byte-by-byte Description of file: table1.dat
Bytes Format Units Label Explanations
1- 22 A22 --- ID Label 25- 34 F10.6 deg RAdeg Right ascension (J2000) 37- 46 F10.6 deg DEdeg Declination (J2000) 49- 54 F6.3 mag Jmag ?=99.999 VVV J magnitude 57- 62 F6.3 mag Ksmag ?=99.999 VVV Ks magnitude 65- 71 F7.2 km/s HRV Heliocentric radial velocity 74- 79 F6.2 km/s e_HRV Heliocentric radial velocity error 82- 86 F5.2 [Sun] [Fe/H] Metallicity
Acknowledgements: Manuela Zoccali, mzoccali(at)astro.puc.cl References: Zoccali et al., Paper I 2014A&A...562A..66Z, Cat. J/A+A/562/A66 Gonzalez et al., Paper II 2015A&A...584A..46G, Cat. J/A+A/584/A46 Vasquez et al., CaT calibration 2015A&A...580A.121V, Cat. J/A+A/580/A121
(End) Manuela Zoccali [IA-PUC., Chile], Patricia Vannier [CDS] 22-Feb-2017
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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