J/ApJ/617/1091 La and Eu abundances in 85 stars (Simmerer+, 2004)
The rise of the s-process in the Galaxy.
Simmerer J., Sneden C., Cowan J.J., Collier J., Woolf V.M., Lawler J.E.
<Astrophys. J., 617, 1091-1114 (2004)>
=2004ApJ...617.1091S 2004ApJ...617.1091S
ADC_Keywords: Abundances ; Stars, population II
Keywords: Galaxy: disk - Galaxy: evolution - Galaxy: halo - stars: abundances -
stars: kinematics - stars: Population II
Abstract:
From newly obtained high-resolution, high signal-to-noise ratio
spectra the abundances of the elements La and Eu have been determined
over the stellar metallicity range -3<[Fe/H]<+0.3 in 159 giant and
dwarf stars. Lanthanum is predominantly made by the s-process in the
solar system, while Eu owes most of its solar system abundance to the
r-process. The changing ratio of these elements in stars over a wide
metallicity range traces the changing contributions of these two
processes to the Galactic abundance mix.
Description:
Spectra were obtained with the McDonald Observatory 2.7m telescope,
using the "2d coude" cross-dispersed echelle spectrograph configured
to a 2 pixel resolving power of R∼60,000 and a Tektronix 2048x2048
CCD.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 81 85 La abundances
table4.dat 63 85 Eu abundances
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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- 10 A10 --- Name Star name
12- 16 F5.2 [---] A3988 ? Log of the 3988Å La line abundance (G1)
18- 22 F5.2 [---] A3995 ? Log of the 3995Å La line abundance (G1)
24- 28 F5.2 [---] A4086 ? Log of the 4086Å La line abundance (G1)
30- 34 F5.2 [---] A4123 ? Log of the 4123Å La line abundance (G1)
36- 40 F5.2 [---] A4333 ? Log of the 4333Å La line abundance (G1)
42- 46 F5.2 [---] A4662 ? Log of the 4662Å La line abundance (G1)
48- 52 F5.2 [---] A5122 ? Log of the 5122Å La line abundance (G1)
54- 58 F5.2 [---] A5303 ? Log of the 5303Å La line abundance (G1)
60- 64 F5.2 [---] A5797 ? Log of the 5797Å La line abundance (G1)
66- 70 F5.2 [---] A6930 ? Log of the 6930Å La line abundance (G1)
72- 76 F5.2 [---] Avg(La) Log of the average La abundance (G1)
78- 81 F4.2 [---] e_Avg(La) The 1σ error in Avg(La)
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- Name Star name
12- 16 F5.2 [---] A3918 ? Log of the 3918Å Eu line abundance (G1)
18- 22 F5.2 [---] A3907 ? Log of the 3907Å Eu line abundance (G1)
24- 28 F5.2 [---] A4129 ? Log of the 4129Å Eu line abundance (G1)
30- 34 F5.2 [---] A4205 ? Log of the 4205Å Eu line abundance (G1)
36- 40 F5.2 [---] A6437 ? Log of the 6437Å Eu line abundance (G1)
42- 46 F5.2 [---] A6645 ? Log of the 6645Å Eu line abundance (G1)
48- 52 F5.2 [---] A7217 ? Log of the 7217Å Eu line abundance (G1)
54- 58 F5.2 [---] Avg(Eu) ? Log of the average Eu abundance (G1)
60- 63 F4.2 [---] e_Avg(Eu) ? The 1σ error in Avg(Eu)
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Global Notes:
Note (G1): Where the abundance is log10(NX/NH)+12 (scale H=12).
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Marianne Brouty [CDS] 24-Aug-2005