J/ApJ/765/157 Abundances of red giants in the Galactic bulge (Johnson+, 2013)
Metallicity distribution functions, radial velocities, and alpha element
abundances in three off-axis bulge fields.
Johnson C.I., Rich R.M., Kobayashi C., Kunder A., Pilachowski C.A.,
Koch A., de Propris R.
<Astrophys. J., 765, 157 (2013)>
=2013ApJ...765..157J 2013ApJ...765..157J
ADC_Keywords: Stars, giant ; Abundances ; Radial velocities ;
Photometry, infrared ; Milky Way
Keywords: Galaxy: bulge; Galaxy: stellar content; stars: abundances;
stars: general; stars: Population II
Abstract:
We present radial velocities and chemical abundance ratios of [Fe/H],
[O/Fe], [Si/Fe], and [Ca/Fe] for 264 red giant branch stars in three
Galactic bulge off-axis fields located near (l,b)=(-5.5,-7), (-4,-9),
and (+8.5,+9). The results are based on equivalent width and spectrum
synthesis analyses of moderate resolution (R~18000), high
signal-to-noise ratio (S/N∼75-300pixel-1) spectra obtained with the
Hydra spectrographs on the Blanco 4m and WIYN 3.5m telescopes. The
targets were selected from the blue side of the giant branch to avoid
cool stars that would be strongly affected by CN and TiO; however, a
comparison of the color-metallicity distribution in literature samples
suggests that our selection of bluer targets should not present a
significant bias against metal-rich stars.
Description:
The observations for this project were obtained between 2011 August
19-20 with the WIYN 3.5m telescope at Kitt Peak National Observatory
and 2011 September 8-12 with the Blanco 4m telescope at Cerro Tololo
Inter-American Observatory. WIYN was used to observe the northern
bulge field centered near (l,b)=(+8.5,+9) and Blanco was used to
observe the two southern bulge fields centered near (l,b)=(-5.5,-7)
and (-4,-9). For WIYN-Hydra, we achieve a resolving power of R∼18000
with wavelength coverage ranging from about 6050-6350Å. For
Blanco-Hydra, we achieve R∼18000 in the setup 6125-6345Å and
R∼15000 in the setup 6550-6840Å.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 79 264 Star identifiers, photometry, model atmosphere
parameters, and radial velocities
table3.dat 48 264 Chemical abundance ratios
table5.dat 58 264 Abundance uncertainty: iron
table6.dat 58 264 Abundance uncertainty: oxygen
table7.dat 58 264 Abundance uncertainty: silicon
table8.dat 58 264 Abundance uncertainty: calcium
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See also:
VII/233 : The 2MASS Extended sources (IPAC/UMass, 2003-2006)
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
J/A+A/549/A147 : Abundances of microlensed Bulge stars. V. (Bensby+, 2013)
J/A+A/546/A57 : Spectroscopy of red giants in the Bulge (Uttenthaler+, 2012)
J/ApJ/749/175 : Abundances for stars in Plaut's window (Johnson+, 2012)
J/A+A/534/A80 : Bulge clump giants metallicity in Baade's window (Hill+, 2011)
J/A+A/533/A134 : Abundances of microlensed stars in the Bulge (Bensby+, 2011)
J/A+A/530/A54 : Abundances of 650 bulge red giants (Gonzalez+, 2011)
J/ApJ/732/108 : Abundances of 92 giants in Plaut's window (Johnson+, 2011)
J/A+A/513/A35 : Abundances of Galactic red giants (Alves-Brito+, 2010)
J/A+A/512/A41 : Abundances of microlensed stars in the Bulge (Bensby+, 2010)
J/A+A/486/177 : Bulge field stars from FLAMES-GIRAFFE spectra (Zoccali+, 2008)
J/A+A/465/799 : Abundances of Galactic Bulge red giants (Lecureur+, 2007)
J/MNRAS/367/1329 : Elemental abundances for 176 stars (Reddy+, 2006)
J/ApJ/636/821 : Abundances of Baade's Window K giants (Fulbright+, 2006)
J/AJ/131/431 : Abundances of Galactic G dwarfs (Brewer+, 2006)
J/A+A/442/281 : Late-type giants phot. & Teff calibration (Kucinskas+, 2005)
J/A+A/433/185 : Abundance analysis of 102 F and G dwarfs (Bensby+, 2005)
J/A+A/410/527 : Abundances in the Galactic disk (Bensby+, 2003)
J/MNRAS/340/304 : [X/Fe] of Galactic disc F and G dwarfs (Reddy+, 2003)
J/AJ/120/1841 : Halo & Disk Stars Abundances (Fulbright 2000)
J/A+A/326/751 : Chemical composition of halo and disk stars (Nissen+, 1997)
J/A+A/275/101 : Galactic disk chemical evolution. I. (Edvardsson+ 1993)
http://irsa.ipac.caltech.edu/applications/DUST/ : Galactic DUST reddening page
http://atlas.obs-hp.fr/elodie/ : ELODIE archive of stellar spectra
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 7 A7 --- Field Observation field (l,b)
9- 24 A16 --- 2MASS 2MASS identifier (HHMMSSss+DDMMSSs; J2000)
26- 30 F5.3 mag E(B-V) [0.1/0.5] B-V color excess
32- 37 F6.3 mag Jmag [9.7/12.5] 2MASS J-band magnitude
39- 44 F6.3 mag Hmag [9/12] 2MASS H-band magnitude
46- 51 F6.3 mag Ksmag [8.7/11.8] 2MASS Ks-band magnitude
53- 56 I4 K Teff [4005/4690] Effective temperature
58- 61 F4.2 [cm/s2] logg [0.9/2.1] Surface gravity
63- 67 F5.2 [Sun] [Fe/H] [-1.5/0.7] Metallicity
69- 72 F4.2 km/s Vt [1/2.2] Microturbulent velocity
74- 79 F6.1 km/s HRV [-269.5/255.1] Heliocentric radial velocity
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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- 7 A7 --- Field Observation field (l,b)
9- 24 A16 --- 2MASS 2MASS identifier (HHMMSSss+DDMMSSs; J2000)
26- 30 F5.2 [Sun] [Fe/H] [-1.5/0.7] Metallicity
32- 36 F5.2 [Sun] [O/Fe] [-0.4/1]? [O/Fe] abundance ratio
38- 42 F5.2 [Sun] [Si/Fe] [-0.6/0.9]? [Si/Fe] abundance ratio
44- 48 F5.2 [Sun] [Ca/Fe] [-0.4/0.6]? [Ca/Fe] abundance ratio
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 7 A7 --- Field Observation field (l,b)
9- 24 A16 --- 2MASS 2MASS identifier (HHMMSSss+DDMMSSs; J2000)
26- 30 F5.2 [-] dFe(T) [-0.04/0.1]? Fe abundance (logε(Fe))
variation for a variation ΔTeff=+100K
32- 36 F5.2 [-] dFe(g) [-0.01/0.2]? Fe abundance variation for a
variation of gravity Δlog(g)=+0.3cgs
38- 42 F5.2 [-] dFe(M) [0/0.1]? Fe abundance variation for a metallicity
variation Δ[M/H]=+0.3dex
44- 48 F5.2 [-] dFe(Vt) [-0.2/0]? Fe abundance variation for a
variation ΔVt=+0.3km/s
50- 53 F4.2 [-] sigFe [0.02/0.1]? σ/N0.5 error for Fe abundance
55- 58 F4.2 [-] D(Fe) [0.1/0.3]? Total Fe abundance uncertainty
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Byte-by-byte Description of file: table6.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 7 A7 --- Field Observation field (l,b)
9- 24 A16 --- 2MASS 2MASS identifier (HHMMSSss+DDMMSSs; J2000)
26- 30 F5.2 [-] dO(T) [0.01/0.03]? O abundance (logε(O))
variation for a variation ΔTeff=+100K
32- 36 F5.2 [-] dO(g) [0.1/0.2]? O abundance variation for for a
variation of gravity Δlog(g)=+0.3cgs
38- 42 F5.2 [-] dO(M) [0.1/0.2]? [O/H] variation for a metallicity
variation Δ[M/H]=+0.3dex
44- 48 F5.2 [-] dO(Vt) [-0.06/0]? O abundance variation for a
variation ΔVt=+0.3km/s
50- 53 F4.2 [-] sigO [0.05/0.05]? σ/N0.5 value for O abundance
55- 58 F4.2 [-] D(O) [0.1/0.3]? Total uncertainty for O abundance
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Byte-by-byte Description of file: table7.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 7 A7 --- Field Observation field (l,b)
9- 24 A16 --- 2MASS 2MASS identifier (HHMMSSss+DDMMSSs; J2000)
26- 30 F5.2 [-] dSi(T) [-0.2/0.01]? Si abundance (logε(Si))
variation for a variation ΔTeff=+100K
32- 36 F5.2 [-] dSi(g) [0.03/0.2]? Si abundance variation for a
variation of gravity Δlog(g)=+0.3cgs
38- 42 F5.2 [-] dSi(M) [0.01/0.1]? [Si/H] variation for a metallicity
variation Δ[M/H]=+0.3dex
44- 48 F5.2 [-] dSi(Vt) [-0.1/-0.01]? Si abundance variation for a
variation ΔVt=+0.3km/s
50- 53 F4.2 [-] sigSi [0/0.3]? σ/N0.5 value for Si abundance
55- 58 F4.2 [-] D(Di) [0.06/0.4]? Total uncertainty for Si abundance
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Byte-by-byte Description of file: table8.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 7 A7 --- Field Observation field (l,b)
9- 24 A16 --- 2MASS 2MASS identifier (HHMMSSss+DDMMSSs; J2000)
26- 30 F5.2 [-] dCa(T) [0.06/0.2]? Ca abundance (logε(Ca))
variation for a variation ΔTeff=+100K
32- 36 F5.2 [-] dCa(g) [-0.04/0.02]? Ca abundance variation for a
variation of gravity Δlog(g)=+0.3cgs
38- 42 F5.2 [-] dCa(M) [-0.03/0.1]? [Ca/H] variation for a metallicity
variation Δ[M/H]=+0.3dex
44- 48 F5.2 [-] dCa(Vt) [-0.3/-0.05]? Ca abundance variation for a
variation ΔVt=+0.3km/s
50- 53 F4.2 [-] sigCa [0/0.2]? σ/N0.5 value for Ca abundance
55- 58 F4.2 [-] D(Ca) [0.1/0.3]? Total uncertainty for Ca abundance
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History:
From electronic version of the journal
(End) Emmanuelle Perret [CDS] 05-Nov-2014