J/MNRAS/435/3667 Equivalent widths of 6 NGC5694 stars (Mucciarelli+, 2013)
NGC 5694: another foster son of the Galactic halo.
Mucciarelli A., Bellazzini M., Catelan M., Dalessandro E., Amigo P.,
Correnti M., Cortes C., D'Orazi V.
<Mon. Not. R. Astron. Soc., 435, 3667-3680 (2013)>
=2013MNRAS.435.3667M 2013MNRAS.435.3667M
ADC_Keywords: Clusters, globular ; Equivalent widths
Keywords: techniques: spectroscopic - stars: abundances -
globular clusters: individual: NGC 5694
Abstract:
We present the results of the analysis of high-resolution spectra
obtained with UVES-FLAMES at the Very Large Telescope for six red
giant branch stars in the outer-halo metal-poor ([Fe/H]I=-1.98 and
[Fe/H]II=-1.83) Galactic globular cluster NGC 5694, which has been
suggested as a possible incomer by Lee et al. based on the anomalous
chemical composition of a single cluster giant. We obtain accurate
abundances for a large number of elements and we find that (a)the six
target stars have the same chemical composition within the
uncertainties, except for Na and Al; (b) the average cluster abundance
of α elements (with the only exception of Si) is nearly solar,
at odds with typical halo stars and globular clusters of similar
metallicity; (c) Y, Ba, La and Eu abundances are also significantly
lower than in Galactic field stars and star clusters of similar
metallicity. Hence, we confirm the Lee et al. classification of NGC
5694 as a cluster of extragalactic origin. We provide the first
insight on the Na-O and Mg-Al anticorrelations in this cluster: all
the considered stars have very similar abundance ratios for these
elements, except one that has significantly lower [Na/Fe] and [Al/Fe]
ratios, suggesting that some degree of early self-enrichment has
occurred also in this cluster.
Description:
The data have been acquired with the FLAMES@VLT spectrograph in the
combined MEDUSA+UVES mode, allowing the simultaneous allocation of
eight UVES high-resolution fibres (discussed in this paper) and 132
MEDUSA mid-resolution fibres (discussed in a forthcoming paper, mainly
devoted to the internal kinematics of the cluster). The employed
spectral configuration for the UVES targets discussed in this paper is
the 580 Red Arm, with a spectral resolution of ∼40000 and covering the
range ∼4800-6800Å. A total of eight exposures of 46min each for the
same targets configuration has been secured in Service Mode during the
period between 2012 April and July.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 71 6 Fundamental parameters for target stars
table2.dat 50 1104 Atomic data and measured EWs of the UVES targets
--------------------------------------------------------------------------------
See also:
J/A+AS/82/71 : Deep photometry of NGC 5694 and Terzan 8 (Ortolani+, 1990)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- ID [37/105] Target number
5- 7 I3 --- G95 [28/110] Identification in Geisler et al,
1995AJ....109..605G 1995AJ....109..605G
9- 19 F11.7 deg RAdeg Right ascension (J2000)
21- 31 F11.7 deg DEdeg Declination (J2000)
33- 38 F6.3 mag Bmag [17.0/17.6] B magnitude
40- 45 F6.3 mag Vmag [15.6/16.6] V magnitude
47- 52 F6.1 km/s RV [-152/-136] Radial velocity
54- 56 F3.1 km/s e_RV [0.3/0.5] rms uncertainty on RV
58- 61 I4 K Teff [4180/4596] Effective temperature
63- 66 F4.2 [cm/s2] logg [0.6/1.3] Surface gravity
68- 71 F4.2 km/s vt [1.6/1.9] Microturbulent velocity ξ
--------------------------------------------------------------------------------
Byte-by-byte Description of file:table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 A8 --- --- [NGC5694-]
9- 11 I3 --- ID [37/105] Target number
13- 18 F6.1 0.1nm lambda [4873/6807] Wavelength (Å)
20- 24 A5 --- Ion Element and ionization stage
26- 31 F6.3 [-] loggf Oscillator strength
33- 37 F5.3 eV chi Energy potential χ
39- 44 F6.2 0.1pm EW Line equivalent width (mÅ)
46- 50 F5.2 0.1pm e_EW rms uncertainty on EW (mÅ)
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 12-Oct-2014