J/AJ/143/14 Lick indices of M31 globular clusters (Schiavon+, 2012)
Star clusters in M31.
IV. A comparative analysis of absorption line indices in old M31 and Milky Way
clusters.
Schiavon R.P., Caldwell N., Morrison H., Harding P., Courteau S.,
MacArthur L.A., Graves G.J.
<Astron. J., 143, 14 (2012)>
=2012AJ....143...14S 2012AJ....143...14S
ADC_Keywords: Galaxies, nearby ; Clusters, globular ; Spectroscopy ; Abundances
Keywords: galaxies: abundances - galaxies: formation -
galaxies: individual (M31) - galaxies: star clusters: general -
globular clusters: general
Abstract:
We present absorption line indices measured in the integrated spectra
of globular clusters both from the Galaxy and from M31. Our samples
include 41 Galactic globular clusters, and more than 300 clusters in
M31. The conversion of instrumental equivalent widths into the Lick
system is described, and zero-point uncertainties are provided.
Comparison of line indices of old M31 clusters and Galactic globular
clusters suggests an absence of important differences in chemical
composition between the two cluster systems. In particular, CN indices
in the spectra of M31 and Galactic clusters are essentially consistent
with each other, in disagreement with several previous works. We
reanalyze some of the previous data, and conclude that reported CN
differences between M31 and Galactic clusters were mostly due to data
calibration uncertainties. Our data support the conclusion that the
chemical compositions of Milky Way and M31 globular clusters are not
substantially different, and that there is no need to resort to
enhanced nitrogen abundances to account for the optical spectra of M31
globular clusters.
Description:
This is the fourth of a series of papers dedicated to analyzing the
kinematics and chemistry of a large sample of M31 GCs, based on
spectra. The M31 GC spectra were obtained using the multi-fiber
spectrograph Hectospec attached to the 6.5m MMT (Multiple Mirror
Telescope). The projected diameter of a Hectospec fiber on the sky is
1.5 deg. The data for M31 GCs come from spectra described by Caldwell
et al. (2009, Cat. J/AJ/137/94).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table9.dat 258 313 Lick indices for M31 globular clusters
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See also:
J/AJ/114/1488 : Globulars in M31 (Holland+ 1997)
J/AcA/48/455 : Globular clusters in M31 and M33 (Mochejska+, 1998)
J/AJ/123/2490 : RV & [Fe/H] of M31 globular cluster system (Perrett+, 2002)
J/A+A/416/917 : Revised Bologna Catalog of M31 GCs (Galleti+, 2004)
J/ApJS/160/176 : Lick/IDS spectral indices and MW and M31 GCs (Lee+, 2005)
J/AJ/133/2764 : M31 globular clusters structural parameters (Barmby+, 2007)
J/AJ/134/706 : New globular clusters in M 31 (Kim+, 2007)
J/A+A/471/127 : New globular clusters in M31 (Galleti+, 2007)
J/ApJS/177/174 : Star clusters in M31 (Narbutis+, 2008)
J/AJ/137/94 : Star clusters in M31. Paper I. (Caldwell+, 2009)
J/A+A/507/1375 : HST/ACS VI data of M31 globular clusters (Perina+, 2009)
J/A+A/508/1285 : Metallicity of M31 globular clusters (Galleti+, 2009)
J/ApJ/704/385 : M31 integrated light abundances (Colucci+, 2009)
J/MNRAS/406/165 : Comparison of Lick indexes (Johansson+, 2010)
J/MNRAS/402/803 : M31 globular cluster system (Peacock+, 2010)
J/AJ/140/1043 : GCs in M31 and the Galaxy (van den Bergh+, 2010)
J/AJ/141/61 : Star clusters in M31. II. (Caldwell+, 2011)
J/A+A/544/A155 : M31 globular clusters (Federici+, 2012)
J/A+A/549/A60 : Ages and [Fe/H] of M31 globular clusters (Cezario+, 2013)
Byte-by-byte Description of file: table9.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- ID Globular cluster identifier
12- 17 F6.3 mag CN1 Lick CN1 index
19- 23 F5.3 mag e_CN1 Uncertainty in CN1
25- 30 F6.3 mag CN2 Lick CN2 index
32- 36 F5.3 mag e_CN2 Uncertainty in CN2
38- 42 F5.2 0.1nm Ca4227 Lick Ca4227 index (Å)
44- 47 F4.2 0.1nm e_Ca4227 Uncertainty in Ca4227 (Å)
49- 53 F5.2 0.1nm G4300 Lick G4300 index (Å)
55- 58 F4.2 0.1nm e_G4300 Uncertainty in G4300 (Å)
60- 64 F5.2 0.1nm Fe4383 Lick Fe4383 index (Å)
66- 69 F4.2 0.1nm e_Fe4383 Uncertainty in Fe4383 (Å)
71- 75 F5.2 0.1nm Ca4455 Lick Ca4455 index (Å)
77- 80 F4.2 0.1nm e_Ca4455 Uncertainty in Ca4455 (Å)
82- 86 F5.2 0.1nm Fe4531 Lick Fe4531 index (Å)
88- 91 F4.2 0.1nm e_Fe4531 Uncertainty in Fe4531 (Å)
93- 97 F5.2 0.1nm C24668 Lick C24668 index (Å)
99-102 F4.2 0.1nm e_C24668 Uncertainty in C24668 (Å)
104-107 F4.2 0.1nm Hb Lick Hβ index (Å)
109-112 F4.2 0.1nm e_Hb Uncertainty in Hb (Å)
114-118 F5.2 0.1nm Fe5015 Lick Fe5015 index (Å)
120-123 F4.2 0.1nm e_Fe5015 Uncertainty in Fe5015 (Å)
125-131 F7.4 mag Mg1 Lick Mg1 index
133-138 F6.4 mag e_Mg1 Uncertainty in Mg1
140-145 F6.4 mag Mg2 Lick Mg2 index
147-152 F6.4 mag e_Mg2 Uncertainty in Mg2
154-158 F5.2 0.1nm Mgb Lick Mgb index (Å)
160-163 F4.2 0.1nm e_Mgb Uncertainty in Mgb (Å)
165-168 F4.2 0.1nm Fe5270 Lick Fe5270 index (Å)
170-173 F4.2 0.1nm e_Fe5270 Uncertainty in Fe5270 (Å)
175-179 F5.2 0.1nm Fe5335 Lick Fe5335 index (Å)
181-184 F4.2 0.1nm e_Fe5335 Uncertainty in Fe5335 (Å)
186-190 F5.2 0.1nm Fe5406 Lick Fe5406 index (Å)
192-195 F4.2 0.1nm e_Fe5406 Uncertainty in Fe5406 (Å)
197-201 F5.2 0.1nm Fe5709 Lick Fe5709 index (Å)
203-206 F4.2 0.1nm e_Fe5709 Uncertainty in Fe5709 (Å)
208-212 F5.2 0.1nm Fe5782 Lick Fe5782 index (Å)
214-217 F4.2 0.1nm e_Fe5782 Uncertainty in Fe5782 (Å)
219-223 F5.2 0.1nm NaD Lick NaD index (Å)
225-228 F4.2 0.1nm e_NaD Uncertainty in NaD (Å)
230-236 F7.4 mag TiO1 Lick TiO1 index
238-243 F6.4 mag e_TiO1 Uncertainty in TiO1
245-251 F7.4 mag TiO2 Lick TiO2 index
253-258 F6.4 mag e_TiO2 Uncertainty in TiO2
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History:
From electronic version of the journal
References:
Caldwell et al. Paper I. 2009AJ....137...94C 2009AJ....137...94C Cat. J/AJ/137/94
Caldwell et al. Paper II. 2011AJ....141...61C 2011AJ....141...61C Cat. J/AJ/141/61
Morrison et al. Paper III. 2011ApJ...726L...9M 2011ApJ...726L...9M
Strader et al. Paper V. 2011AJ....142....8S 2011AJ....142....8S
(End) Greg Schwarz [AAS], Sylvain Guehenneux [CDS] 05-Apr-2013