J/AJ/133/270 Metallicities and ages in Leo II dSph (Koch+, 2007)
Complexity on small scales.
II. Metallicities and ages in the Leo II dwarf spheroidal galaxy.
Koch A., Grebel E.K., Kleyna J.T., Wilkinson M.I., Harbeck D.R.,
Gilmore G.F., Wyse R.F.G., Evans N.W.
<Astron. J., 133, 270-283 (2007)>
=2007AJ....133..270K 2007AJ....133..270K
ADC_Keywords: Galaxies, nearby ; Photometry, SDSS ; Abundances
Keywords: galaxies: abundances - galaxies: dwarf - galaxies: evolution -
galaxies: individual (Leo II) - galaxies: stellar content -
galaxies: structure - Local Group
Abstract:
We present metallicities and ages for 52 red giants in the remote
Galactic dwarf spheroidal (dSph) galaxy Leo II. These stars cover the
entire surface area of Leo II and are radial velocity members. We
obtained medium-resolution multifiber spectroscopy with FLAMES as part
of a Large Program with the Very Large Telescope at the European
Southern Observatory, Chile. The metallicities were determined based
on the well-established near-infrared Ca II triplet technique.
Description:
Our observations of Leo II were taken as part of the European Southern
Observatory (ESO) Large Program 171.B-0520(A), which aims at
elucidating the kinematic and chemical characteristics of Galactic
dSphs. Five fields in Leo II were observed with FLAMES at ESO's Very
Large Telescope (VLT).
We refer the reader to Paper I (Koch et al., 2006, Cat. J/AJ/131/895
for details on observing strategy, data reduction, and calibration
techniques.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 83 52 Measured properties of radial velocity members
in Leo II
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See also:
J/AJ/131/895 : Stars in the Carina dwarf spheroidal galaxy (Koch+, 2006)
Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- [KGK2007] Star identification
6- 7 I2 h RAh Hour of Right Ascension (J2000)
9- 10 I2 min RAm Minute of Right Ascension (J2000)
12- 15 F4.1 s RAs Second of Right Ascension (J2000)
17 A1 --- DE- Sign of Declination (J2000)
18- 19 I2 deg DEd Degree of Declination (J2000)
21- 22 I2 arcmin DEm Arcminute of Declination (J2000)
24- 25 I2 arcsec DEs Arcsecond of Declination (J2000)
27- 30 F4.2 arcmin r Elliptical radius
32- 36 F5.2 mag Vmag Johnson-Cousins V band magnitude
38- 42 F5.2 mag gmag SDSS g band magnitude (1)
44- 47 F4.2 mag g-r SDSS (g-r) color index (1)
49- 52 F4.2 mag g-i SDSS (g-i) color index (1)
54- 57 F4.2 0.1nm W' Reduced Ca II triplet width in Angstroms
59- 62 F4.2 0.1nm e_W' Uncertainty in W'
64- 68 F5.2 --- [Fe/H] Derived [Fe/H] abundance (2)
70- 73 F4.2 --- e_[Fe/H] Uncertainty in [Fe/H] (2)
75- 78 F4.1 Gyr Age ? Derived age
80 I1 Gyr e_Age ? Lower limit uncertainty in Age
82- 83 I2 Gyr E_Age ? Upper limit uncertainty in Age
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Note (1): Given in the photometric system of the SDSS.
Note (2): [Fe/H] and the respective uncertainty are on the scale of
Carretta & Gratton (1997, Cat. J/A+AS/121/95) and given
following eq. 7.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Patricia Vannier [CDS] 11-Dec-2008