J/ApJ/788/39 Hot Jupiter exoplanets host stars EW and abundances (Teske+, 2014)
C/O ratios of stars with transiting hot Jupiter exoplanets.
Teske J.K., Cunha K., Smith V.V., Schuler S.C., Griffith C.A.
<Astrophys. J., 788, 39 (2014)>
=2014ApJ...788...39T 2014ApJ...788...39T (SIMBAD/NED BibCode)
ADC_Keywords: Stars, double and multiple ; Planets ; Equivalent widths ;
Abundances
Keywords: planets and satellites: formation - stars: abundances -
stars: atmospheres
Abstract:
The relative abundances of carbon and oxygen have long been recognized
as fundamental diagnostics of stellar chemical evolution. Now, the
growing number of exoplanet observations enable estimation of these
elements in exoplanetary atmospheres. In hot Jupiters, the C/O ratio
affects the partitioning of carbon in the major observable molecules,
making these elements diagnostic of temperature structure and
composition. Here we present measurements of carbon and oxygen
abundances in 16 stars that host transiting hot Jupiter exoplanets,
and we compare our C/O ratios to those measured in larger samples of
host stars, as well as those estimated for the corresponding exoplanet
atmospheres. With standard stellar abundance analysis we derive
stellar parameters as well as [C/H] and [O/H] from multiple abundance
indicators, including synthesis fitting of the [O I] λ6300 line
and non-LTE corrections for the O I triplet. Our results, in agreement
with recent suggestions, indicate that previously measured exoplanet
host star C/O ratios may have been overestimated. The mean transiting
exoplanet host star C/O ratio from this sample is 0.54 (C/O☉=0.54),
versus previously measured C/O_host star_ means of ∼0.65-0.75. We also
observe the increase in C/O with [Fe/H] expected for all stars based
on Galactic chemical evolution; a linear fit to our results falls
slightly below that of other exoplanet host star studies but has a
similar slope. Though the C/O ratios of even the most-observed
exoplanets are still uncertain, the more precise abundance analysis
possible right now for their host stars can help constrain these
planets' formation environments and current compositions.
Description:
Our target list was chosen to include some of the best-studied hot Jupiter
host stars that are observable from the Northern Hemisphere, as well as a
range of planet radii, masses, and orbital periods. All but three of
the planetary hosts in this sample have at least the 3.6 um, 4.5 um,
5.8 um, and 8.0 um diagnostic measurements of secondary eclipse depth from
the Spitzer Infrared Array Camera (IRAC; Fazio et al. 2004ApJS..154...10F 2004ApJS..154...10F).
These data cover wavelengths with features of CH4, CO, CO2, and
H2O, which are the most abundant oxygen and carbon molecules in hot
Jupiter atmospheres. There are three sources of observations for this
project: the High Dispersion Spectrograph (HDS; Noguchi et al.
2002PASJ...54..855N 2002PASJ...54..855N) on the 8.2 m Subaru Telescope at Mauna Kea
Observatory, the High Resolution Echelle Spectrometer (HIRES; Vogt et al.
1994SPIE.2198..362V 1994SPIE.2198..362V) at the Keck I Telescope, and the Keck/HIRES archive.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
stars.dat 48 17 Stars
table4.dat 246 106 Lines Measured, Equivalent Widths,
and Abundances
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See also:
III/211 : Keck/HIRES Sky Line Atlas (Osterbrock+ 1997)
J/A+A/415/1153 : [Fe/H] for 98 extra-solar planet-host stars (Santos+, 2004)
J/A+A/458/997 : Abundances for 6 transiting planet host stars (Santos+, 2006)
J/AJ/141/11 : Spitzer observations of planet-host stars
(Dodson-Robinson+, 2011)
J/A+A/558/A106 : Chemical abundances for 83 transit hosts (Mortier+, 2013)
Byte-by-byte Description of file: stars.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- Name Host star's name
11- 12 I2 h RAh Simbad Hour of Right Ascension (J2000)
14- 15 I2 min RAm Simbad Minute of Right Ascension (J2000)
17- 21 F5.2 s RAs Simbad Second of Right Ascension (J2000)
23 A1 --- DE- Simbad Sign of the Declination (J2000)
24- 25 I2 deg DEd Simbad Degree of Declination (J2000)
27- 28 I2 arcmin DEm Simbad Arcminute of Declination (J2000)
30- 33 F4.1 arcsec DEs Simbad Arcsecond of Declination (J2000)
35- 39 F5.2 mag Vmag V band magnitude from Table 1
41- 48 A8 --- Name1 Host star's name as written in table4.dat file
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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- 5 A5 --- Ion Ion designation (1)
7- 13 F7.2 0.1nm Wave Wavelength, in Angstroms
15- 18 F4.2 eV ExPot Excitation Potential
20- 25 F6.3 [-] log(gf) Log of oscillator strength
27- 30 F4.1 10-13m EWSolHDSI ? Solar equivalent width (2)
32- 36 F5.2 10-13m EWSolHDSSP ? Solar equivalent width (3)
38- 41 F4.1 10-13m EWSolHIRSP ? Solar equivalent width (4)
43- 46 F4.2 [-] logNSolHDSI ? Log of solar number abundance (2)
48- 51 F4.2 [-] logNSolHDSS ? Log of solar number abundance (3)
53- 56 F4.2 [-] logNSolHIRS ? Log of solar number abundance (4)
58- 61 F4.1 10-13m EW-COROT2 ? CoRoT-2 equivalent width (4)
63- 66 F4.2 [-] logN-COROT2 ? Log of CoRoT-2 number abundance (4)
68- 72 F5.1 10-13m EW-TRES4 ? TrES-4 equivalent width (4)
74- 77 F4.2 [-] logN-TRES4 ? Log of TrES-4 number abundance (4)
79- 82 F4.1 10-13m EW-TRES2 ? TrES-2 equivalent width (4)
84- 87 F4.2 [-] logN-TRES2 ? Log of TrES-2 number abundance (4)
89- 93 F5.1 10-13m EW-WASP2 ? WASP-2 equivalent width (4)
95- 98 F4.2 [-] logN-WASP2 ? Log of WASP-2 number abundance (4)
100-104 F5.1 10-13m EW-WASP12 ? WASP-12 equivalent width (3)
106-109 F4.2 [-] logN-WASP12 ? Log of WASP-12 number abundance (3)
111-115 F5.1 10-13m EW-HD149026 ? HD 149026 equivalent width (3)
117-120 F4.2 [-] logN-HD149026 ? Log of HD 149026 number abundance (3)
122 A1 --- f_EW-HD149026 [*] Flag on EW-HD149026 (5)
124-127 F4.1 10-13m EW-HATP1 ? HAT-P-1 equivalent width (4)
129-132 F4.2 [-] logN-HATP1 ? Log of HAT-P-1 number abundance (4)
134-138 F5.1 10-13m EW-XO2S ? XO-2S equivalent width (2)
140-143 F4.2 [-] logN-XO2S ? Log of XO-2S number abundance (2)
145-149 F5.1 10-13m EW-XO2N ? XO-2N equivalent width (2)
151-154 F4.2 [-] logN-XO2N ? Log of XO-2N number abundance (2)
156-159 F4.1 10-13m EW-XO1 ? XO-1 equivalent width (2)
161-164 F4.2 [-] logN-XO1 ? Log of XO-1 number abundance (2)
166-169 F4.1 10-13m EW-TRES3 ? TRES-3 equivalent width (3)
171-174 F4.2 [-] logN-TRES3 ? Log of TRES-3 number abundance (3)
176 A1 --- f_EW-TRES3 [*] Flag on EW-TRES3 (5)
178-182 F5.1 10-13m EW-HD189733 ? HD 189733 equivalent width (2)
184-187 F4.2 [-] logN-HD189733 ? Log of HD 189733 number abundance (2)
189 A1 --- f_EW-HD189733 [*] Flag on EW-HD189733 (5)
191-195 F5.1 10-13m EW-HD80606 ? HD 80606 equivalent width (3)
197-200 F4.2 [-] logN-HD80606 ? Log of HD 80606 number abundance (3)
202-206 F5.1 10-13m EW-HATP7 ? HAT-P-7 equivalent width (3)
208-211 F4.2 [-] logN-HATP7 ? Log of HAT-P-7 number abundance (3)
213 A1 --- f_EW-HATP7 [*] Flag on EW-HATP7 (5)
215-219 F5.1 10-13m EW-HATP13 ? HAT-P-13 equivalent width (2)
221-224 F4.2 [-] logN-HATP13 ? Log of HAT-P-13 number abundance (2)
226-230 F5.1 10-13m EW-HATP16 ? HAT-P-16 equivalent width (4)
232-235 F4.2 [-] logN-HATP16 ? Log of HAT-P-16 number abundance (4)
237-241 F5.1 10-13m EW-WASP32 ? WASP-32 equivalent width (4)
243-246 F4.2 [-] logN-WASP32 ? Log of WASP-32 number abundance (4)
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Note (1): For [O I] (6300.30), the log N values represent those derived from
synthesis fitting, as these are the values we use in calculating the
final [O/H] for each object. The reported EWs refer to the total EW
of the 6300.3 Angstrom blend.
Note (2): Measured with IRAF in Subaru/HDS data. EWs in milliAngstroms.
Note (3): Measured with SPECTRE in Subaru/HDS data. EWs in milliAngstroms.
Note (4): Measured with SPECTRE in Keck/HIRES data. EWs in milliAngstroms.
Note (5): Flag as follows:
* = Measured with SPECTRE in Keck/HIRES data.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Tiphaine Pouvreau [CDS] 04-Jul-2017