J/A+A/305/245 Fe I in metal-poor stars (Magain+, 1996)
Empirical study of departures from the excitation equilibrium of Fe I in
metal-poor stars
Magain P., Zhao G.
<Astron. Astrophys. 305, 245 (1996)>
=1996A&A...305..245M 1996A&A...305..245M (SIMBAD/NED BibCode)
ADC_Keywords: Abundances ; Equivalent widths ;
Keywords: stars: abundances; population II - Galaxy: abundances
Description:
A detailed analysis of neutral iron lines in a sample of 13 metal-poor
dwarfs and subgiants is carried out on the basis of high resolution
spectra obtained with the ESO Coude Echelle Spectrometer. The deduced
iron abundance is found to depend on the excitation potential of the
line used, higher excitation lines generally indicating higher
abundances. This could be caused by departures from the local
thermodynamic equilibrium (LTE) or by temperature inhomogeneities in
the stellar atmospheres. The dependency of this effect on the stellar
atmospheric parameters is investigated. From the comparison of iron
lines with lines of other elements, it is concluded that the low
excitation Fe I lines are much more affected than the high excitation
lines. The consequences of these effects for the classical abundance
analyses are examined. It is found that they may explain, at least in
part, some previously reported discrepancies between the results of
different authors.
Objects:
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RA (2000) DE Name
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00 38 31.8 -08 18 07 HD 3567
04 01 42.6 -57 12 45 HD 25704
14 01 03.9 -38 02 59 HD 122196
14 30 12.7 -62 51 41 HD 126793
14 59 51.6 -22 00 20 HD 132475
17 00 46.7 -64 33 01 HD 152924
17 42 49.5 -40 18 55 HD 160617
18 16 27.3 -59 24 04 HD 166913
20 01 01.2 -12 15 02 HD 189558
20 23 33.8 -21 21 22 HD 193901
20 26 11.4 +09 27 28 HD 194598
20 40 49.1 -18 47 13 HD 196892
20 58 07.7 -48 12 01 HD 199289
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table4 178 36 Equivalent widths and abundances
table4.tex 114 103 LaTeX version of table4
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Byte-by-byte Description of file: table4
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Bytes Format Units Label Explanations
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1- 3 A3 --- Element Element
6- 12 F7.2 0.1nm Lambda Line wavelength
16- 19 F4.1 0.1pm EW3567 []? Equivalent width for the star HD 3567
21- 25 F5.3 --- Ab3567 []? Abundance for the star HD 3567 (1)
27- 30 F4.1 0.1pm EW25704 []? Equivalent width for the star HD 25704
32- 36 F5.3 --- Ab25704 []? Abundance for the star HD 25704 (1)
40- 43 F4.1 0.1pm EW122196 []? Equivalent width for the star HD 122196
45- 49 F5.3 --- Ab122196 []? Abundance for the star HD 122196 (1)
53- 56 F4.1 0.1pm EW126793 []? Equivalent width for the star HD 126793
58- 62 F5.3 --- Ab126793 []? Abundance for the star HD 126793 (1)
67- 70 F4.1 0.1pm EW132475 []? Equivalent width for the star HD 132475
72- 76 F5.3 --- Ab132475 []? Abundance for the star HD 132475 (1)
78- 81 F4.1 0.1pm EW152924 []? Equivalent width for the star HD 152924
83- 87 F5.3 --- Ab152924 []? Abundance for the star HD 152924 (1)
92- 95 F4.1 0.1pm EW160617 []? Equivalent width for the star HD 160617
97-101 F5.3 --- Ab160617 []? Abundance for the star HD 160617 (1)
106-109 F4.1 0.1pm EW166913 []? Equivalent width for the star HD 166913
111-115 F5.3 --- Ab166913 []? Abundance for the star HD 166913 (1)
117-120 F4.1 0.1pm EW189558 []? Equivalent width for the star HD 189558
122-126 F5.3 --- Ab189558 []? Abundance for the star HD 189558 (1)
130-133 F4.1 0.1pm EW193901 []? Equivalent width for the star HD 193901
135-139 F5.3 --- Ab193901 []? Abundance for the star HD 193901 (1)
143-146 F4.1 0.1pm EW194598 []? Equivalent width for the star HD 194598
148-152 F5.3 --- Ab194598 []? Abundance for the star HD 194598 (1)
157-160 F4.1 0.1pm EW196892 []? Equivalent width for the star HD 196892
162-166 F5.3 --- Ab196892 []? Abundance for the star HD 196892 (1)
168-171 F4.1 0.1pm EW199289 []? Equivalent width for the star HD 199289
173-177 F5.3 --- Ab199289 []? Abundance for the star HD 199289 (1)
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Note (1): Abundance = log[Element/H]+12
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(End) Simona Mei [CDS] 07-Jun-1995