J/A+A/508/L17 Abundances in solar analogs (Ramirez+, 2009)
Accurate abundance patterns of solar twins and analogs. Does the anomalous solar
chemical composition come from planet formation?
Ramirez I., Melendez J., Asplund M.
<Astron. Astrophys., 508, L17-L20 (2009)>
=2009A&A...508L..17R 2009A&A...508L..17R
ADC_Keywords: Stars, G-type ; Stars, dwarfs ; Abundances
Keywords: stars: abundances - Sun: abundances - planetary systems
Abstract:
We derive the abundance of 19 elements in a sample of 64 stars with
fundamental parameters very similar to solar, which minimizes the
impact of systematic errors in our spectroscopic 1D-LTE differential
analysis, using high-resolution (R∼60000), high signal-to-noise ratio
(S/N∼200) spectra. The estimated errors in the elemental abundances
relative to solar are as small as ∼0.025dex. The abundance ratios
[X/Fe] as a function of [Fe/H] agree closely with previously
established patterns of Galactic thin-disk chemical evolution.
Description:
Our sample stars were selected from the Hipparcos catalog (I/239) by
applying constraints on color, based on the color-Teff calibrations by
Ramirez & Melendez (2005ApJ...626..465R 2005ApJ...626..465R), corrected by suspected zero
point errors (Casagrande et al., 2009, submitted), trigonometric
parallaxes, and literature values for [Fe/H] and chromospheric
activity, if available. About 100 stars satisfied our selection
criteria and, given our observational constraints, data for 64 of them
were acquired. We also observed the asteroids Vesta and Ceres as solar
reference.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 55 64 Derived stellar parameters, average abundance
ratios [X/Fe] of volatile elements (<900K), and
slope of the [X/Fe] vs. Tc relation for
refractory elements (>900K)
abund.dat 240 64 Abundance ratios [X/Fe] for C, O, Na, Al, Si, S,
Ca, Sc, Ti, V, Cr, Mn, Ni, Cu, Zn, Y, Zr, and Ba
(tables 2-4 of the paper)
--------------------------------------------------------------------------------
See also:
I/239 : The Hipparcos and Tycho Catalogues (ESA 1997)
J/A+A/468/663 : Li abundances in solar-analog stars (Takeda+, 2007)
J/ApJS/181/62 : Survey of young solar analogs (Metchev+, 2009)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 I6 --- HIP HIP star number
8- 11 I4 K Teff Effective temperature
13- 16 F4.2 [cm/s2] logg Surface gravity
18- 23 F6.3 [Sun] [Fe/H] Metallicity
25- 29 F5.3 [Sun] e_[Fe/H] rms uncertainty on [Fe/H] (1)
31- 36 F6.3 [Sun] [X/Fe] Average [X/Fe] value for volatile elements
(Tc<900K)
38- 42 F5.3 [Sun] e_[X/Fe] rms uncertainty on [X/Fe]
44- 49 F6.3 K-1 dA/dT Slope of the [X/Fe] vs. Tc relation for
refractory elements (Tc>900K)
51- 55 F5.3 K-1 e_dA/dT rms uncertainty on slope
--------------------------------------------------------------------------------
Note (1): Errors in [Fe/H] correspond to the 1-σ scatter of the
line-by-line abundances.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: abund.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 I6 --- HIP HIP star number
8- 13 F6.3 [Sun] [C/Fe] Abundance ratio [C/Fe]
15- 19 F5.3 [Sun] e_[C/Fe] rms uncertainty on [C/Fe] (1)
21- 26 F6.3 [Sun] [O/Fe] Abundance ratio [O/Fe]
28- 32 F5.3 [Sun] e_[O/Fe] rms uncertainty on [O/Fe] (1)
34- 39 F6.3 [Sun] [Na/Fe] ? Abundance ratio [Na/Fe]
41- 45 F5.3 [Sun] e_[Na/Fe] ? rms uncertainty on [Na/Fe] (1)
47- 52 F6.3 [Sun] [Al/Fe] Abundance ratio [Al/Fe]
54- 58 F5.3 [Sun] e_[Al/Fe] rms uncertainty on [Al/Fe] (1)
60- 65 F6.3 [Sun] [Si/Fe] Abundance ratio [Si/Fe]
67- 71 F5.3 [Sun] e_[Si/Fe] rms uncertainty on [Si/Fe] (1)
73- 78 F6.3 [Sun] [S/Fe] ? Abundance ratio [S/Fe]
80- 84 F5.3 [Sun] e_[S/Fe] ? rms uncertainty on [S/Fe] (1)
86- 91 F6.3 [Sun] [Ca/Fe] Abundance ratio [Ca/Fe]
93- 97 F5.3 [Sun] e_[Ca/Fe] rms uncertainty on [Ca/Fe] (1)
99-104 F6.3 [Sun] [Sc/Fe] ? Abundance ratio [Sc/Fe]
106-110 F5.3 [Sun] e_[Sc/Fe] ? rms uncertainty on [Sc/Fe] (1)
112-117 F6.3 [Sun] [Ti/Fe] Abundance ratio [Ti/Fe]
119-123 F5.3 [Sun] e_[Ti/Fe] rms uncertainty on [Ti/Fe] (1)
125-130 F6.3 [Sun] [V/Fe] Abundance ratio [V/Fe]
132-136 F5.3 [Sun] e_[V/Fe] rms uncertainty on [V/Fe] (1)
138-143 F6.3 [Sun] [Cr/Fe] Abundance ratio [Cr/Fe]
145-149 F5.3 [Sun] e_[Cr/Fe] rms uncertainty on [Cr/Fe] (1)
151-156 F6.3 [Sun] [Mn/Fe] ? Abundance ratio [Mn/Fe]
158-162 F5.3 [Sun] e_[Mn/Fe] ? rms uncertainty on [Mn/Fe] (1)
164-169 F6.3 [Sun] [Ni/Fe] Abundance ratio [Ni/Fe]
171-175 F5.3 [Sun] e_[Ni/Fe] rms uncertainty on [Ni/Fe] (1)
177-182 F6.3 [Sun] [Cu/Fe] ? Abundance ratio [Cu/Fe]
184-188 F5.3 [Sun] e_[Cu/Fe] ? rms uncertainty on [Cu/Fe] (1)
190-195 F6.3 [Sun] [Zn/Fe] Abundance ratio [Zn/Fe]
197-201 F5.3 [Sun] e_[Zn/Fe] rms uncertainty on [Zn/Fe] (1)
203-208 F6.3 [Sun] [Y/Fe] ? Abundance ratio [Y/Fe]
210-214 F5.3 [Sun] e_[Y/Fe] ? rms uncertainty on [Y/Fe] (1)
216-221 F6.3 [Sun] [Zr/Fe] ? Abundance ratio [Zr/Fe]
223-227 F5.3 [Sun] e_[Zr/Fe] ? rms uncertainty on [Zr/Fe] (1)
229-234 F6.3 [Sun] [Ba/Fe] Abundance ratio [S/Bae]
236-240 F5.3 [Sun] e_[Ba/Fe] rms uncertainty on [Ba/Fe] (1)
--------------------------------------------------------------------------------
Note (1): Errors correspond to the 1-σ scatter of the line-by-line
abundances. A conservative value of 0.050 for the error was assumed
when only one line was available.
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 08-Mar-2010