J/ApJ/725/2349 C/O vs Mg/Si of planetary systems (Delgado Mena+, 2010)
Chemical clues on the formation of planetary systems: C/O versus Mg/Si for HARPS
GTO sample.
Delgado Mena E., Israelian G., Gonzalez Hernandez J.I., Bond J.C.,
Santos N.C., Udry S., Mayor M.
<Astrophys. J., 725, 2349-2358 (2010)>
=2010ApJ...725.2349D 2010ApJ...725.2349D
ADC_Keywords: Abundances ; Effective temperatures ; Planets ;
Stars, double and multiple ; Stars, late-type
Keywords: planetary systems - planets and satellites: formation -
stars: abundances - stars: atmospheres - stars: fundamental parameters
Abstract:
Theoretical studies suggest that C/O and Mg/Si are the most important
elemental ratios in determining the mineralogy of terrestrial planets.
The C/O ratio controls the distribution of Si among carbide and oxide
species, while Mg/Si gives information about the silicate mineralogy.
We present a detailed and uniform study of C, O, Mg, and Si abundances
for 61 stars with detected planets and 270 stars without detected
planets from the homogeneous high-quality unbiased HARPS GTO sample,
together with 39 more planet-host stars from other surveys. We
determine these important mineralogical ratios and investigate the
nature of the possible terrestrial planets that could have formed in
those planetary systems. We find mineralogical ratios quite different
from those of the Sun, showing that there is a wide variety of
planetary systems which are not similar to our solar system. Many
planetary host stars present an Mg/Si value lower than 1, so their
planets will have a high Si content to form species such as MgSiO3.
This type of composition can have important implications for planetary
processes such as plate tectonics, atmospheric composition, or
volcanism.
Description:
The HARPS GTO sample is composed of 451 FGK stars selected from a
volume-limited stellar sample observed by the CORALIE spectrograph at
La Silla observatory. For more details we point the reader to a
description of the sample by Mayor et al. (2003Msngr.114...20M 2003Msngr.114...20M). This
sample is composed of high resolution, high signal-to-noise spectra
for 71 stars with planets and 380 with no known giant planets. Precise
stellar parameters were taken from Sousa et al. (2008, Cat.
J/A+A/487/373), with uncertainties of the order of 30K for Teff,
0.06dex for logg, 0.08km/s for ξt, and 0.03dex for [Fe/H].
To improve the statistics we added high-quality spectroscopic
observations for 42 stars hosting planets from the CORALIE survey.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 70 61 Stars with planets from the HARPS GTO survey
table2.dat 70 39 Stars with planets from other surveys
table3.dat 70 270 Comparison sample stars from HARPS GTO survey
--------------------------------------------------------------------------------
See also:
J/A+A/541/A40 : Metallicity of solar-type stars (Maldonado+, 2012)
J/A+A/536/A71 : Atmospheric parameters of nearby giant stars (Jones+, 2011)
J/A+A/526/A71 : C abundances in G and K nearby stars (Da Silva+, 2011)
J/A+A/533/A141 : Stellar parameters for 582 HARPS FGK stars (Sousa+, 2011)
J/ApJ/720/1290 : Abundances of stars hosting planets (Ghezzi+, 2010)
J/ApJ/720/1592 : Signatures of terrestrial planets (Hernandez+, 2010)
J/ApJ/715/1050 : Predicted abundances for extrasolar planets. I. (Bond+, 2010)
J/A+A/497/563 : Chemical abundances of 451 stars (Neves+, 2009)
J/A+A/487/373 : Spectroscopic parameters of 451 HARPS-GTO stars (Sousa+, 2008)
J/A+A/469/783 : Code for automatic determination of EW (ARES) (Sousa+, 2007)
J/PASJ/59/335 : Properties of 160 F-K disk dwarfs/subgiants (Takeda+, 2007)
J/MNRAS/378/1141 : Chemical abundances in 31 stars (Gonzalez+, 2007)
J/MNRAS/370/163 : Abundance distribution of stars with planets (Bond+, 2006)
J/A+A/449/723 : Abundances in atmospheres of stars with planets (Gilli+, 2006)
J/ApJ/622/1102 : The planet-metallicity correlation. (Fischer+, 2005)
J/A+A/438/251 : Abundances in stars with giant planets (Beirao+, 2005)
J/A+A/415/391 : The CORALIE survey for extrasolar planets. XII (Mayor+, 2004)
J/A+A/415/155 : Oxygen abundances in the Galactic disk (Bensby+, 2004)
J/A+A/415/1153 : [Fe/H] for 98 extra-solar planet-host stars (Santos+, 2004)
J/A+A/398/1121 : Abundances of A-F stars (Erspamer+, 2003)
J/A+A/390/235 : OI and FeII EWs in metal-poor stars (Nissen+ 2002)
Byte-by-byte Description of file: table[123].dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 A9 --- Name Star identification (HDNNNNNNA)
11- 14 I4 K Teff Effective temperature
16- 19 F4.2 [cm/s2] log(g) Log of the surface gravity
21- 24 F4.2 km/s Vt Microturbulence velocity (ξt)
26- 30 F5.2 [Sun] [Fe/H] Metallicity
32- 36 F5.2 [Sun] [O/H] Log of Oxygen/Hydrogen number abundance (1)
38- 42 F5.2 [Sun] [Ni/H] Log of Nickel/Hydrogen number abundance (1)
44- 48 F5.2 [Sun] [C/H] Log of Carbon/Hydrogen number abundance (1)
50- 54 F5.2 [Sun] [Mg/H] Log of Magnesium/Hydrogen number abundance (1)
56- 60 F5.2 [Sun] [Si/H] Log of Silicon/Hydrogen number abundance (1)
62- 65 F4.2 --- C/O Carbon/Oxygen absolute abundance ratio
67- 70 F4.2 --- Mg/Si Magnesium/Silicon absolute abundance ratio
--------------------------------------------------------------------------------
Note (1): Relative to the Sun.
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 13-Aug-2012