J/A+A/583/A94 [X/Fe] scatter derived for spectral lines (Adibekyan+, 2015)
Identifying the best iron-peak and alpha-capture elements for chemical tagging:
The impact of the number of lines on measured scatter?
Adibekyan V., Figueira P., Santos N.C., Sousa S.G., Faria J.P.,
Delgado-Mena E., Oshagh M., Tsantaki M., Hakobyan A.A.,
Gonzalez Hernandez J.I., Suarez-Andres L., Israelian G.
<Astron. Astrophys. 583, A94 (2015)>
=2015A&A...583A..94A 2015A&A...583A..94A (SIMBAD/NED BibCode)
ADC_Keywords: Stars, nearby ; Abundances, peculiar
Keywords: stars: abundances - Stars: general - stars: fundamental parameters
Abstract:
The main goal of this work is to explore which elements carry the most
information about the birth origin of stars and, as such, which are
best suited for chemical tagging. We explored different techniques to
minimize the effect of outlier value lines in the abundances by using
Ni abundances derived for 1111 FGK-type stars. We evaluate how the
limited number of spectral lines can affect the final chemical
abundance. Then we make an efficient even footing comparison of the
[X/Fe] scatter between the elements that have a different number of
observable spectral lines in the studied spectra. When several
spectral lines are available, we find that the most efficient way of
calculating the average abundance of elements is to use a weighted
mean (WM), whereby we consider the distance from the median abundance
as a weight. This method can be used effectively without removing
suspected outlier lines. When the same number of lines are used to
determine chemical abundances, we show that the [X/Fe] star-to-star
scatter for iron group and alpha-capture elements is almost the same.
The largest scatter among the studied elements, was observed for Al
and the smallest for Cr and Ni. We recommend caution when comparing
[X/Fe] scatters among elements where a different number of spectral
lines are available. A meaningful comparison is necessary to identify
elements that show the largest intrinsic scatter, which can then be
used limit of [X/H] are very abrupt.
Description:
The file elfe.dat presents the [X/Fe] star-to-star scatter derived for
each individual line.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
elfe.dat 18 161 Atomic number, wavelength of lines, and [X/Fe]
scatter derived for each line
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See also:
J/MNRAS/450/1900 : Chemical abundances of 257 giant stars (Adibekyan+, 2015)
J/A+A/497/563 : Chemical abundances of 451 stars (Neves+, 2009)
Byte-by-byte Description of file: elfe.dat
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Bytes Format Units Label Explanations
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1- 4 F4.1 ---- El Atomic number
6- 12 F7.2 0.1nm lambda Central wavelength
14- 18 F5.3 [Sun] Scatter Star-to-star [X/Fe] scatter
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Acknowledgements:
Vardan Adibekyan, Vardan.Adibekyan(at)astro.up.pt
(End) Vardan Adibekyan [CAUP], Patricia Vannier [CDS] 15-Oct-2015