J/ApJ/655/492 Equivalent widths of 26 metal-poor stars (Aoki+, 2007)
Carbon-enhanced metal-poor stars. I. Chemical compositions of 26 stars.
Aoki W., Beers T.C., Christlieb N., Norris J.E., Ryan S.G., Tsangarides S.
<Astrophys. J., 655, 492-521 (2007)>
=2007ApJ...655..492A 2007ApJ...655..492A
ADC_Keywords: Stars, metal-deficient ; Spectroscopy ; Photometry
Keywords: nuclear reactions, nucleosynthesis, abundances - stars: abundances -
stars: AGB and post-AGB - stars: carbon -stars: Population II
Abstract:
The chemical compositions of 26 metal-poor stars that exhibit strong
CH and/or C2 molecular bands are determined. Twenty-two stars in our
sample satisfy our definition for carbon-enhanced metal-poor (CEMP)
stars based on the carbon abundance ratio ([C/Fe]) and the
evolutionary status. In addition, we measure Na abundances for nine
known carbon-enhanced stars. Combining our new sample with the results
of previous work, we investigate the abundance and evolutionary status
of a total of 64 CEMP stars.
Description:
High-resolution spectroscopic observations for the stars in our sample
were obtained with Subaru HDS, with a spectral resolving power R=50000
(a slit width of 0.72"), in 2002 October and 2003 May.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 93 26 Object list and observing log
table2.dat 79 26 Photometric Data
ew.dat 43 3954 Equivalent widths (tables 5-7 of the paper)
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See also:
J/A+A/404/187 : Equivalent widths for metal-poor stars (Gratton+, 2003)
J/A+A/425/671 : Equivalent widths of 10 metal-poor halo stars (Bai+, 2004)
J/A+A/440/321 : Chemical abundances in 43 metal-poor stars (Jonsell+, 2005)
J/AJ/130/2804 : Carbon abundances in metal-poor stars (Rossi+, 2005)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- Seq Sequential number
4- 15 A12 --- Name Star name
16 A1 --- n_Name [b] Note on CS 29497-034 (1)
18- 19 I2 h RAh Right ascension (J2000.0)
21- 22 I2 min RAm Right ascension (J2000.0)
24- 27 F4.1 s RAs Right ascension (J2000.0)
29 A1 --- DE- Declination sign (J2000.0)
30- 31 I2 deg DEd Declination (J2000.0)
33- 34 I2 arcmin DEm Declination (J2000.0)
36- 37 I2 arcsec DEs Declination (J2000.0)
39- 42 I4 s ExpTime Exposure time
44- 48 I5 ct Count Counts in 5200Å
50- 59 A10 "YYYY/MM/DD" Obs.date Observation date (UT)
61- 67 F7.2 km/s RV ? Radial velocity
69- 72 F4.2 km/s e_RV ? Standard error on RV (2)
74- 77 I4 s ExpTime2 ? Exposure time for Obs.dat2
79- 82 I4 ct Count2 ? Counts in 5200Å for Obs.dat2
84- 93 A10 "YYYY/MM/DD" Obs.dat2 ? Second observation date (UT)
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Note (1): b = CS 29497-034 = HE 0039-2635.
Note (2): Standard error of radial velocity sigma/sqrt(n), where sigma is
the standard deviation of the values from individual lines and n is
the number of lines used.
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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- 2 I2 --- Seq Sequential number
4- 15 A12 --- Name Star name
17- 22 F6.3 mag Bmag Johnson B magnitude
24- 29 F6.3 mag Vmag Johnson V magnitude
31- 36 F6.3 mag Rmag Cousins R magnitude
38- 43 F6.3 mag Imag Cousins I magnitude
45- 50 F6.3 mag Jmag Johnson J magnitude
52- 57 F6.3 mag Hmag Johnson H magnitude
59- 64 F6.3 mag Kmag Johnson K magnitude
66- 69 F4.2 mag E(B-V) Reddening
71- 74 I4 K Teff Effective temperature from (V-K) colour index
76- 79 I4 K DTeff Difference in effective temperature (1)
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Note (1): DTeff=Teff(V-K)0-<Teff(V-R)0, Teff(V-I)0, Teff(R-I)0>
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Byte-by-byte Description of file: ew.dat
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Bytes Format Units Label Explanations
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1- 12 A12 --- Name Star name
14- 18 A5 --- Ion Species identification
20- 26 F7.2 0.1nm Lambda Wavelength in Angstroms
28- 31 F4.2 eV LEP Excitation potential
33- 37 F5.2 [-] log(gf) Log of the oscillator strength
39- 43 F5.1 10-13m EW1 ? Equivalent width (1)
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Note (1): In units of milliAngstroms.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Patricia Vannier [CDS] 10-Dec-2008