J/A+A/615/A165 Equivalent widths of 13 red giants in IC 4756 (Bagdonas+, 2018)
Chemical composition of giant stars in the open cluster IC 4756.
Bagdonas V., Drazdauskas A., Tautvaisiene G., Smiljanic R., Chorniy Y.
<Astron. Astrophys. 615, A165 (2018)>
=2018A&A...615A.165B 2018A&A...615A.165B (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, open ; Stars, horizontal branch ; Abundances ;
Equivalent widths
Keywords: stars: abundances -
open clusters and associations: individual: IC 4756 -
stars: horizontal-branch - stars: evolution -
Abstract:
Homogeneous investigations of red giant stars in open clusters
contribute to studies of internal evolutionary mixing processes inside
stars, which are reflected in abundances of mixing-sensitive chemical
elements like carbon, nitrogen, and sodium, while α- and
neutron-capture element abundances are useful in tracing the Galactic
chemical evolution.
The main aim of this study is a comprehensive chemical analysis of red
giant stars in the open cluster IC 4756, including determinations of
12C/13C and C/N abundance ratios, and comparisons of the results
with theoretical models of stellar and Galactic chemical evolution.
We used a classical differential model atmosphere method to analyse
high-resolution spectra obtained with the FEROS spectrograph on the
2.2m MPG/ESO Telescope. The carbon, nitrogen, and oxygen abundances,
12C/13C ratios, and neutron-capture element abundances were
determined using synthetic spectra, and the main atmospheric
parameters and abundances of other chemical elements were determined
from equivalent widths of spectral lines.
Description:
Equivalent widths (EWs) of spectral lines in stars of IC 4756 are
presented. The table provides the data for stars 12, 14, 28, 38, 42,
44, 52, 69, 81, 101, 109, 125, 164 (among which 14, 28, 44, and 52 are
doubtful members). The identifications of stars were adopted from
Kopff (1943). For each star, the EWs for Na, Mg, Al, Si, Ca, Sc, Ti,
Cr, and Ni are given. For the measurement of EWs, a SPLAT-VO program
package (Skoda et al., 2014A&C.....7..108S 2014A&C.....7..108S) was used.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 57 13 A list of analysed stars and their parameters
table2.dat 64 143 The equivalent widths for individual lines in
stars of IC 4756
--------------------------------------------------------------------------------
See also:
J/AJ/109/1903 : Membership to cluster IC 4756 (Missana+ 1995)
J/AJ/134/1216 : Abundances of NGC 7142, 6939 and IC 4756 stars (Jacobson+ 2007)
J/A+A/515/A28 : Abundances of dwarfs and giants in 2 open clusters (Pace+ 2010)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- ID Star identification number,
IC 4665 NNN in Simbad (1)
5- 12 F8.4 deg RAdeg Right ascension (J2000)
14- 20 F7.4 deg DEdeg Declination (J2000)
22- 25 F4.2 mag Vmag V magnitude (2)
27- 30 F4.2 mag B-V B-V colour index (2)
32- 41 A10 "date" Obs.Date Observation date
43- 45 I3 s ExpTime Exposure time
47- 52 F6.2 km/s RV Radial velocity (3)
54 A1 --- l_S/N [~] Limit flag on S/N
55- 57 I3 --- S/N Signal-to-noise ration at ∼64000Å
--------------------------------------------------------------------------------
Note (1): The IDs are adopted from Kopff (1943AN....274...69K 1943AN....274...69K).
Note (2): The UBV photometry are taken from Alcaino (1965LowOB...6..167A 1965LowOB...6..167A).
Note (3): The radial velocities as determined in this work.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 A4 --- El Element
6- 12 F7.2 0.1nm lambda Wavelength
14- 16 I3 0.1pm EW12 ? Equivalent widths for star 12
18- 20 I3 0.1pm EW14 ? Equivalent widths for star 14
22- 24 I3 0.1pm EW28 ? Equivalent widths for star 28
26- 28 I3 0.1pm EW38 ? Equivalent widths for star 38
30- 32 I3 0.1pm EW42 ? Equivalent widths for star 42
34- 36 I3 0.1pm EW44 ? Equivalent widths for star 44
38- 40 I3 0.1pm EW52 ? Equivalent widths for star 52
42- 44 I3 0.1pm EW69 ? Equivalent widths for star 69
46- 48 I3 0.1pm EW81 ? Equivalent widths for star 81
50- 52 I3 0.1pm EW101 ? Equivalent widths for star 101
54- 56 I3 0.1pm EW109 ? Equivalent widths for star 109
58- 60 I3 0.1pm EW125 ? Equivalent widths for star 125
62- 64 I3 0.1pm EW164 ? Equivalent widths for star 164
--------------------------------------------------------------------------------
Acknowledgements:
Vilius Bagdonas, vilius.bagdonas(at)ff.vu.lt
(End) Vilius Bagdonas [Vilnius University], Patricia Vannier [CDS] 16-Apr-2018