J/AJ/153/136 Planets and their host stars with Gaia parallaxes (Stassun+, 2017)
Accurate empirical radii and masses of planets and their host stars with Gaia
parallaxes.
Stassun K.G., Collins K.A., Gaudi B.S.
<Astron. J., 153, 136 (2017)>
=2017AJ....153..136S 2017AJ....153..136S (SIMBAD/NED BibCode)
ADC_Keywords: Exoplanets ; Stars, distances ; Effective temperatures ;
Abundances, [Fe/H] ; Morphology ; Stars, diameters ; Spectroscopy
Keywords: astronomical databases: miscellaneous - methods: data analysis -
planets and satellites: fundamental parameters -
stars: fundamental parameters
Abstract:
We present empirical measurements of the radii of 116 stars that host
transiting planets. These radii are determined using only direct
observables - the bolometric flux at Earth, the effective temperature,
and the parallax provided by the Gaia first data release - and thus are
virtually model independent, with extinction being the only free
parameter. We also determine each star's mass using our newly
determined radius and the stellar density, a virtually model independent
quantity itself from previously published transit analyses. These
stellar radii and masses are in turn used to redetermine the
transiting-planet radii and masses, again using only direct observables.
The median uncertainties on the stellar radii and masses are 8% and
30%, respectively, and the resulting uncertainties on the planet radii
and masses are 9% and 22%, respectively. These accuracies are generally
larger than previously published model-dependent precisions of 5% and
6% on the planet radii and masses, respectively, but the newly
determined values are purely empirical. We additionally report radii
for 242 stars hosting radial-velocity (non-transiting) planets, with a
median achieved accuracy of ∼2%. Using our empirical stellar masses we
verify that the majority of putative "retired A stars" in the sample
are indeed more massive than ∼1.2 M☉. Most importantly, the
bolometric fluxes and angular radii reported here for a total of 498
planet host stars-with median accuracies of 1.7% and 1.8%,
respectively-serve as a fundamental data set to permit the
re-determination of transiting-planet radii and masses with the Gaia
second data release to ∼3% and ∼5% accuracy, better than currently
published precisions, and determined in an entirely empirical fashion.
Description:
We began by selecting all planet-hosting stars found in the
exoplanets.org database (Han et al. 2014PASP..126..827H 2014PASP..126..827H, accessed on
2016 August 31) and added 12 well-characterized transiting planets that
were present in the NASA Exoplanet Archive but missing from exoplanets.org.
We then selected systems with host stars that are also present in the
Tycho-2 catalog (Cat. I/259), resulting in 560 unique stars. Of these,
62 stars were removed because they lacked one or more of the minimal
set of parameters required for our analysis (see Section 2.2); nearly
all of these were Kepler planets for which radial-velocity
semi-amplitudes were not reported. The remaining 498 stars form our
master study sample for which we perform our SED fitting procedures,
resulting in fundamental Fbol and Θ measurements, as discussed
below. The Gaia DR1 (Cat. I/337) provides parallaxes for 358 of these
stars, of which 116 were listed as hosting transiting planets and 242
were listed as hosting radial-velocity planets.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table4.dat 44 498 Gaia parallax data used in this study
table5.dat 158 132 Sample of transiting planets used in this study
table6.dat 158 366 Sample of radial-velocity (non-transiting)
planets used in this study
table7.dat 133 498 Results
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See also:
I/259 : The Tycho-2 Catalogue (Hog+ 2000)
III/231 : The Tycho-2 Spectral Type Catalog (Wright+, 2003)
V/136 : Teff and metallicities for Tycho-2 stars (Ammons+, 2006)
I/337 : Gaia DR1 (Gaia Collaboration, 2016)
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
J/MNRAS/427/343 : Infrared excesses of Hipparcos stars (McDonald+, 2012)
J/A+A/556/A150 : SWEETCat I. Stellar parameters for host stars (Santos+, 2013)
J/A+A/580/A23 : Stroemgren-Crawford uvbyβ photometry catalog
(Paunzen, 2015)
Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- Tycho Tycho identifier
13- 28 A16 --- Name Object Name
30- 36 F7.2 pc Dist [3.56/2519.91]? Gaia derived parallax based
distance
38- 44 F7.2 pc e_Dist [0/2610.42]? Uncertainty in Dist (1)
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Note (1): Random uncertainty only; does not include systematic uncertainty that
is potentially as large as ∼300 µas (see the text).
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Byte-by-byte Description of file: table5.dat table6.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 11 A11 --- Tycho Tycho identifier
13- 28 A16 --- Name Object Name
30- 33 I4 K Teff [3129/7308] Stellar effective temperature
35- 37 I3 K e_Teff [1/200] Uncertainty in Teff
39- 42 F4.2 [cm/s2] logg [1.3/4.92] Surface gravity
44- 47 F4.2 [cm/s2] e_logg [0/0.5]? Uncertainty in logg
49- 53 F5.2 [Sun] [Fe/H] [-0.79/0.63] Metallicity
55- 67 A13 --- Source Source for spectroscopic stellar parameters
(1)
69- 78 F10.5 d Porb [0.35501/5040] Orbital period
80- 86 E7.1 d e_Porb Uncertainty in Porb
88- 91 F4.2 --- e [0/0.97]? Eccentricity
93- 96 F4.2 --- e_e [0/0.23]? Uncertainty in e
98-103 F6.1 m/s KRV [0/1818.3] Radial velocity semi-amplitude
105-109 F5.1 m/s e_KRV [0/295]? Uncertainty in KRV
111-115 F5.2 deg i [79/90]? Inclination (not in table 6)
117-121 F5.2 deg e_i [0/18]? Uncertainty in i (not in table 6)
123-129 E7.1 --- Depth ? Depth of the transit δtr
(not in table 6)
131-137 E7.1 --- e_Depth ? Uncertainty in Depth (not in table 6)
139-143 F5.2 --- a/R* [2.66/98.38]? Ratio of semimajor axis to
stellar radius (not in table 6)
145-148 F4.2 --- e_a/R* [0.01/7.32]? Uncertainty in a/R*
(not in table 6)
150-153 F4.2 AU a [0.03/6.46]? Semimajor axis (not in table 5)
155-158 F4.2 AU e_a [0/2.92]? Uncertainty in a (not in table 5)
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Note (1): Source for spectroscopic stellar parameters as follows:
Ammons = Ammons et al. (2006, Cat. V/136);
EXO = exoplanets.org;
PASTEL = Paunzen (2015, J/A+A/580/A23);
SWEET = Santos et al. (2013, J/A+A/556/A150);
McDonald:2012 = McDonald et al. (2012, J/MNRAS/427/343);
Wright:2003 = Wright et al. (2003, Cat. III/231).
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Byte-by-byte Description of file: table7.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- Tycho Tycho identifier
13- 28 A16 --- Name Object Name
30- 34 F5.2 --- chi2 [0.17/12.09] Reduced χ2 of the SED fit
36- 39 F4.2 mag Av [0/1.4] V band extinction
41- 44 F4.2 mag e_Av [0/0.13] Uncertainty in Av
46- 53 E8.2 mW/m2 Fbol Bolometric flux (in erg/s/cm2)
55- 62 E8.2 mW/m2 e_Fbol Uncertainty in Fbol (in erg/s/cm2)
64- 70 F7.2 uarcsec Theta* [12.54/4910.83] Host angular radius Θ*
72- 77 F6.2 uarcsec e_Theta* [0.26/249.69] Uncertainty in Theta*
79- 83 F5.2 Rsun R* [0.36/71.23]? Host radius
85- 89 F5.2 Rsun e_R* [0.01/73.63]? Uncertainty in R*
91- 94 F4.2 g/cm3 rho* [0.04/3.06]? Host density ρ*
96- 99 F4.2 g/cm3 e_rho* [0.01/1.05]? Uncertainty in rho*
101-105 F5.2 Msun M* [0.17/23.56]? Host mass (1)
107-111 F5.2 Msun e_M* [0.01/97.1]? Uncertainty in M*
113-116 F4.2 Rjup Rp [0.03/3.55]? Planet radius
118-121 F4.2 Rjup e_Rp [0/4.87]? Uncertainty in Rp
123-127 F5.2 Mjup Mp [0.01/55.59]? Planet mass (2)
129-133 F5.2 Mjup e_Mp [0/78.55]? Uncertainty in Mp
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Note (1): For transiting planet hosts, M* is calculated from the direct
observables ρ* and R*. For radial velocity (RV) planet hosts,
M* is calculated from the direct observables logg and R*.
Note (2): For RV planets, Mp is modulo sin(i).
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History:
From electronic version of the journal
(End) Prepared by [AAS], Tiphaine Pouvreau 02-May-2018