J/ApJ/737/9 RAVE spectroscopic data of stars in the thick disk (Ruchti+, 2011)
Observational properties of the metal-poor thick disk of the Milky Way and
insights into its origins.
Ruchti G.R., Fulbright J.P., Wyse R.F.G., Gilmore G.F., Bienayme O.,
Bland-Hawthorn J., Gibson B.K., Grebel E.K., Helmi A., Munari U.,
Navarro J.F., Parker Q.A., Reid W., Seabroke G.M., Siebert A., Siviero A.,
Steinmetz M., Watson F.G., Williams M., Zwitter T.
<Astrophys. J., 737, 9 (2011)>
=2011ApJ...737....9R 2011ApJ...737....9R
ADC_Keywords: Abundances ; Radial velocities ; Stars, giant ; Stars, distances ;
Milky Way
Keywords: Galaxy: abundances - Galaxy: disk - stars: abundances -
stars: late-type
Abstract:
We have undertaken the study of the elemental abundances and kinematic
properties of a metal-poor sample of candidate thick-disk stars
selected from the Radial Velocity Experiment spectroscopic survey of
bright stars to differentiate among the present scenarios of the
formation of the thick disk. In this paper, we report on a sample of
214 red giant branch, 31 red clump/horizontal branch, and 74
main-sequence/sub-giant branch metal-poor stars, which serves to
augment our previous sample of only giant stars. We find that the
thick disk [α/Fe] ratios are enhanced and have little variation
(<0.1dex), in agreement with our previous study. The augmented sample
further allows, for the first time, investigation of the gradients in
the metal-poor thick disk.
Description:
All candidate stars were first selected from the internal RAVE catalog
(Version DR2; see Cat. III/265). Observations were conducted during
the period between 2007 May and 2009 February. All high-resolution
spectra were obtained using one of the following echelle
spectrographs: MIKE on the Magellan-Clay telescope at Las Campanas
Observatory in Chile, FEROS on the MPG 2.2m telescope at ESO La Silla
Observatory in Chile, UCLES on the Anglo-Australian telescope in
Australia, and the ARC echelle spectrograph on the Apache Point 3.5m
telescope in New Mexico. The instrumental setups gave resolving powers
between 35000 and 45000, providing complete spectral coverage from
3500Å to 9500Å, except for UCLES which had complete spectral
coverage between 4460Å and 7270Å.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 55 328 Observational data
table2.dat 68 319 Atmospheric and abundance-ratio data
table3.dat 87 319 Kinematic data
table4.dat 60 319 Orbital parameters
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See also:
III/265 : RAVE 3rd data release (Siebert+, 2011)
J/A+A/522/A54 : Distance determination for RAVE stars. II. (Zwitter+, 2010)
J/A+A/513/A35 : Abundances of Galactic red giants (Alves-Brito+, 2010)
J/A+A/511/A90 : RAVE DR2 distance catalogue (Breddels+, 2010)
J/ApJ/725/L186 : Orbital eccentricities of 31535 G-dwarfs (Dierickx+, 2010)
J/MNRAS/367/1329 : Elemental abundances for 176 stars (Reddy+, 2006)
J/AJ/131/431 : Abundances of Galactic G dwarfs (Brewer+, 2006)
J/A+A/438/139 : Abundances in Milky Way's disk (Soubiran+, 2005)
J/A+A/418/551 : Galactic disk stars abundances & vel. (Mishenina+, 2004)
J/A+A/410/527 : Abundances in the Galactic disk (Bensby+, 2003)
J/A+A/398/141 : Vertical distribution of galactic disk stars (Soubiran+, 2003)
J/AJ/120/1841 : Abundances & Kinematics of Halo & Disk Stars (Fulbright 2000)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 16 A16 --- Name Star name
18- 24 F7.3 deg RAdeg Right Ascension in decimal degrees (J2000)
26- 32 F7.3 deg DEdeg Declination in decimal degrees (J2000)
34- 37 F4.1 mag Imag [9/11.9] RAVE I band magnitude
39- 47 A9 --- Date Observation date; yyyymmdd or yyyycombo (1)
49- 51 A3 --- Obs Observatory code (2)
53- 55 I3 pix-1 S/N [100/280] Estimated signal to noise between
5500-6000Å
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Note (1): 2009combo or 2007combo refers to the combined spectra from two
different nights of the same run. For APO runs, "combo" refers to
combined spectra from different runs.
Note (2): Observatory code as follows:
LCO = Las Campanas Observatory Magellan-Clay telescope
APO = Apache Point 3.5-m telescope;
AAT = Anglo-Australian telescope;
ESO = ESO La Silla Observatory MPG 2.2-m telescope.
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 16 A16 --- Name Star name
18- 21 I4 K Teff [4043/6496] Effective temperature
23- 26 F4.2 [cm/s2] log(g) [0.66/4.44] Log of the surface gravity
28- 32 F5.2 [Sun] [Fe/H] [-2.83/-0.37] Log of the FeII/H abundance ratio
34- 37 F4.1 km/s Vturb [-0.1/5.9] Microturbulent velocity ξ
39- 43 F5.2 [-] [Mg] Log of the Mg/FeI abundance ratio
45- 50 F6.2 [-] [Si] ?=-99.99 Log of the Si/FeI abundance ratio
52- 56 F5.2 [-] [Ca] Log of the Ca/FeI abundance ratio
58- 62 F5.2 [-] [TiI] Log of the TiI/FeI abundance ratio
64- 68 F5.2 [-] [TiII] Log of the TiII/FeII abundance ratio
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 16 A16 --- Name Star name
18- 22 I5 pc Dist [89/15699] Distance
24- 29 F6.1 km/s Vhel [-145.8/248.7] Heliocentric velocity
31- 36 F6.1 km/s Vpi Velocity component in radial direction toward
Galactic center VΠ
38- 42 F5.1 km/s e_Vpi Uncertainty in Vpi
44- 49 F6.1 km/s Vth Velocity component in direction of
Galactic rotation VΘ
51- 55 F5.1 km/s e_Vth Uncertainty in Vth
57- 62 F6.1 km/s VZ Velocity component perpendicular to
Galactic Plane VZ
64- 68 F5.1 km/s e_VZ Uncertainty in VZ
70- 73 F4.2 --- Pthin Thin disk PDF value (1)
75- 78 F4.2 --- Pthick Thick disk PDF value (1)
80- 83 F4.2 --- Phalo Halo PDF value (1)
85- 87 F3.1 --- Pop [1/3] Galactic population assignment (2)
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Note (1): In the analysis, additional intermediate populations were
considered; PDF values are the sum of the probabilities (normalized)
obtained from all Monte Carlo realizations for each Galactic population.
Note (2): Populations are numbered as:
1 = thin disk;
2 = thick disk;
3 = halo
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 16 A16 --- Name Star name
18- 20 I3 --- Norb [2/614] Number of orbits
22- 25 F4.1 kpc Rper.a [0/15.9] Perigalactic radius from all orbits
27- 32 F6.1 kpc Rapo.a Apogalactic radius from all orbits (1)
34- 39 F6.1 kpc Zmax.a Maximum vertical distance from all orbits
41- 44 F4.1 kpc Rper.f Perigalactic radius from final orbit
46- 50 F5.1 kpc Rapo.f Apogalactic radius from final orbit (1)
52- 56 F5.1 kpc Zmax.f Maximum vertical distance from final orbit
58- 60 F3.1 --- e [0/1] Orbit Eccentricity
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Note (1): Stars with Apogalactic radii >100kpc have larger distance errors
and/or high proper motion errors.
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Nomenclature notes:
Star names follow three formats: <CHHMMSSs+DDMMSS>, <JHMMSS.s+DDMMSS> or
<TFFFFNNNNNN>. These objects are in Simbad (See
"RAVE" column in Cat. III/265. <TFFFFNNNNNN> = TYC FFFF NNNNN N.
History:
From electronic version of the journal
References:
Ruchti et al. Thick Disk as Traced by the Alpha Elements. 2010ApJ...721L..92R 2010ApJ...721L..92R
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 07-Jan-2013