J/AJ/142/63 Abundance of five stars in NGC 6397 (Koch+, 2011)
A differential chemical element analysis of the metal-poor globular cluster
NGC 6397.
Koch A., McWilliam A.
<Astron. J., 142, 63 (2011)>
=2011AJ....142...63K 2011AJ....142...63K
ADC_Keywords: Clusters, globular ; Stars, giant ; Abundances
Keywords: globular clusters: individual (NGC 6397) - stars: abundances -
stars: atmospheres - stars: individual (Arcturus, Hip 66815)
Abstract:
We present chemical abundances in three red giants and two turnoff
(TO) stars in the metal-poor Galactic globular cluster (GC) NGC 6397
based on spectroscopy obtained with the Magellan Inamori Kyocera
Echelle high-resolution spectrograph on the Magellan 6.5m Clay
telescope. Our results are based on a line-by-line differential
abundance analysis relative to the well-studied red giant Arcturus and
the Galactic halo field star HIP 66815.
Description:
Observations were carried out over five nights in 2005 May and June
using the Magellan Inamori Kyocera Echelle spectrograph at the 6.5m
Magellan2/Clay telescope.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
stars.dat 100 5 Details of observations, target properties and
atmospheric parameters
table2.dat 33 156 Line list for the red giants
table3.dat 29 133 Line list for the turn-off stars
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See also:
J/A+A/287/769 : UV photometry of NGC 6397 (Burgarella+ 1994)
J/PASP/108/682 : Low-Mass Stars in Outer Field in NGC 6397 (Mould+, 1996)
J/A+AS/122/1 : BV photometry of variables in NGC 6397 (Kaluzny, 1997)
J/AJ/119/1225 : Omega Cen and NGC 6397 Stroemgren photometry (Hughes+, 2000)
J/AJ/120/3111 : Stromgren photometry of NGC 6397 (Anthony-Twarog+, 2000)
J/A+A/425/509 : VI photometry of NGC 6397 (Andreuzzi+, 2004)
J/A+A/490/777 : Abundances of Population II stars in NGC 6397 (Lind+, 2008)
J/AJ/135/2141 : F814W+F606W photometry of NGC 6397 faint stars (Richer+, 2008)
J/A+A/503/545 : Equivalent widths of Li, Na, Fe, Ca in NGC 6397 (Lind+, 2009)
J/A+A/505/L13 : Lithium in globular NGC 6397 (Gonzalez Hernandez+, 2009)
J/ApJ/709/241 : NGC 6397 X-rays sources characterisation (Bogdanov+, 2010)
Byte-by-byte Description of file: stars.dat
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Bytes Format Units Label Explanations
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1- 5 I5 --- ID Star number <Cl* NGC 6397 K NNNNN> in Simbad
7- 9 A3 --- Type Type (RGB or TO=turn-off)
11- 20 A10 "YYYY/MM/DD" Date Observation date
22- 26 I5 s tExp Exposure time
28- 30 I3 pix-1 S/N Signal-to-noise ratio
32- 33 I2 h RAh Right ascension (J2000)
35- 36 I2 min RAm Right ascension (J2000)
38- 41 F4.1 s RAs Right ascension (J2000)
43 A1 --- DE- Declination sign (J2000)
44- 45 I2 deg DEd Declination (J2000)
47- 48 I2 arcmin DEm Declination (J2000)
50- 53 F4.1 arcsec DEs Declination (J2000)
55- 59 F5.2 mag Vmag V magnitude
61- 64 F4.2 mag B-V B-V colour index
66- 69 F4.2 mag V-K V-K colour index
71- 74 F4.1 km/s HV Heliocentric velocity
76- 79 I4 K Teff1 Effective temperature from V-K colour index
81- 84 I4 K Teff2 Effective temperature from spectroscopy
86- 89 I4 K Teff Average effective temperature
90 A1 --- n_Teff [a] other indices used for Teff (1)
92- 95 F4.2 [cm/s2] logg Gravity surface
97-100 F4.2 km/s Vt Microturbulent velocity
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Note (1): a = Average including Teff (Hα) and the other color indices.
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 5 A5 --- Ion Ion designation
7- 13 F7.2 0.1nm lambda Wavelength
15- 18 F4.2 eV ExPot Excitation potential
20- 23 F4.1 0.1pm E13414 ? Equivalent width for star #13414 (in mÅ)
25- 28 F4.1 0.1pm E8958 ? Equivalent width for star #8958 (in mÅ)
30- 33 F4.1 0.1pm E7230 ? Equivalent width for star #7230 (in mÅ)
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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- 5 A5 --- Ion Ion designation
7- 13 F7.2 0.1nm lambda Wavelength
15- 18 F4.2 eV ExPot Excitation potential
20- 24 F5.1 0.1pm E13552 ? Equivalent width for star #13552 (in mÅ)
26- 29 F4.1 0.1pm E365 ? Equivalent width for star #365 (in mÅ)
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Patricia Vannier [CDS] 12-Oct-2012