J/A+A/645/A7 Determining true mass of RV exoplanets with Gaia (Kiefer+, 2021)
Determining the true mass of radial-velocity exoplanets with Gaia - Nine planet
candidates in the brown dwarf or stellar regime and 27 confirmed planets.
Kiefer F., Hebrard G., A. Lecavelier des Etangs, E. Martioli, S. Dalal,
Vidal-Madjar A.
<Astron. Astrophys. 645, A7 (2021)>
=2021A&A...645A...7K 2021A&A...645A...7K (SIMBAD/NED BibCode)
ADC_Keywords: Stars, double and multiple ; Exoplanets ; Binaries, orbits ;
Radial velocities ; Positional data
Keywords: planets and satellites: fundamental parameters - brown dwarfs -
binaries: general - astrometry
Abstract:
Mass is one of the most important parameters for determining the true
nature of an astronomical object. Yet, many published exoplan- ets
lack a measurement of their true mass, in particular those detected as
a result of radial-velocity (RV) variations of their host star. For
those examples, only the minimum mass, or msini, is known, owing to
the insensitivity of RVs to the inclination of the detected orbit
compared to the plane of the sky. The mass that is given in databases
is generally that of an assumed edge-on system (∼90°), but many
other inclinations are possible, even extreme values closer to 0°
(face-on). In such a case, the mass of the published object could be
strongly underestimated by up to two orders of magnitude. In the
present study, we use GASTON, a recently developed tool taking
advantage of the voluminous Gaia astrometric database to constrain the
inclination and true mass of several hundreds of published exoplanet
candidates. We find 9 exoplanet candidates in the stellar or brown
dwarf (BD) domain, among which 6 were never characterized. We show
that 30 Ari B b, HD 141937 b, HD 148427 b, HD 6718 b, HIP 65891 b, and
HD 16760 b have masses larger than 13.5 MJ at 3σ. We also
confirm the planetary nature of 27 exoplanets, including HD 10180 c, d
and g. Studying the orbital periods, eccentricities, and host-star
metallicities in the BD domain, we found distributions with respect to
true masses consistent with other publications. The distribution of
orbital periods shows of a void of BD detections below ∼100d, while
eccentricity and metallicity distributions agree with a transition
between BDs similar to planets and BDs similar to stars in the range
40-50MJ.
Description:
Orbital parameters for 911 RV exoplanet candidates published in the
Exoplanets.org database (Table 2). These are combined with Gaia
archive data from the first data release (DR1) for 659 hosts of 755
exoplanets, in particular the astrometric excess noise (Table 3), to
obtain a constraint on the true mass of these candidates using GASTON.
The astrometric motion of 29 candidates have been firmly detected by
Gaia, constituting the Detection Sample, while other 227
non-transiting candidates, the Non-Detection Sample, do not have a
significant astrometric excess noise. Their orbital and Gaia data are
summarised in Table 5. The results of GASTON true mass derivation for
the 29 companions of the Detection Sample are available in Table 8 in
the paper only, and the GASTON results for 189 companions among the
227 of the Non-Detection Sample are available in Table 9.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 407 911 RV orbital parameters for 911 companions
(exoplanets.org)
table3.dat 234 659 Properties (Simbad) and astrometric data
(DR1 Gaia archive) for 659 host stars of
755 exoplanets (corrected version, 29-Sep-2021)
table5.dat 222 256 RV orbital parameters and Gaia data for 258
exoplanet candidates
table9.dat 96 189 GASTON results for 189 companions from the
non-detection sample
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See also:
I/337 : Gaia DR1 (Gaia Collaboration, 2016)
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 18 A18 --- Name Planet name
20- 38 F19.16 Mjup Msini Mass, Msin(i)
40- 50 F11.9 Mjup e_Msini ? Msin(i) uncertainty
52- 67 F16.11 d Per Orbital period
69- 81 E13.11 d e_Per ? Orbital period uncertainty
83- 91 F9.7 --- ecc Eccentricity
93-103 F11.9 --- e_ecc ? Eccentricity uncertainty
105-114 F10.5 deg omega Periastron longitude
116-125 F10.5 deg e_omega ? Periastron longitude uncertainty
127-144 F18.10 d Tp Time of periastron passage (MJD)
146-167 F22.17 d e_Tp ? Time of periastron passage
uncertainty (MJD)
169-178 F10.5 m/s K RV amplitude
180-189 F10.6 m/s e_K ? RV amplitude uncertainty
191-198 F8.6 Msun Mstar Stellar mass
200-209 F10.8 Msun e_Mstar ? Stellar mass uncertainty
211 I1 --- Drift RV drift flag
213-221 F9.5 m/s O-C ? RV residuals O-C
223 I1 --- Transit Transit flag
225-279 A55 --- Orbit-ref Orbit reference paper
281-331 A51 --- Orbit-url Orbit reference paper URL
333-352 A20 --- Transit-ref Transit reference paper
354-407 A54 --- Transit-url Transit reference paper URL
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 26 A26 --- Name Star name
28- 29 I2 h RAh Right ascension from Simbad (J2000)
31- 32 I2 min RAm Right ascension from Simbad (J2000)
34- 46 F13.10 s RAs Right ascension from Simbad (J2000)
48 A1 ---- DE- Declination from Simbad (J2000)
49- 50 I2 deg DEd Declination from Simbad (J2000)
52- 53 I2 arcmin DEm Declination from Simbad (J2000)
55- 66 F12.9 arcsec DEs Declination from Simbad (J2000)
68- 73 F6.3 mag Vmag ? V-band magnitude from Simbad
75- 80 F6.3 mag B-V ? B-V color magnitude from Simbad
82- 95 A14 --- SpType Spectral Type from Simbad
97-115 F19.16 mag Gmag ? G-band Gaia magnitude from GaiaDR1
117-136 F20.16 mas Plx Parallax (Gaia DR1 or DR2) (G1)
138-156 F19.17 mas e_Plx ? Parallax uncertainty
158-162 F5.1 --- NFoV Number of field-of-view transit
164-167 F4.1 --- Ntot Total number of astrometric measurements
169-173 A5 --- Dataset [false true] Gaia DR1 dataset (G2)
175-179 A5 --- Dup [false true] Duplicate source (G3)
181-200 F20.17 mas epsi1 Astrometric excess noise (G3)
202-223 F22.15 --- sepsi1 EpsilonDR1 significance (G3)
225-234 F10.8 --- (BP-RP)2 Gb-Gr Gaia DR2 color magnitude
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 15 A15 --- Name Planet name
17- 28 F12.7 d P Orbital period
30- 41 F12.7 d e_P Orbital period uncertainty
43- 50 F8.5 Mjup Msini Mass, Msin(i)
52- 58 F7.5 Mjup e_Msini Msin(i) uncertainty
60- 66 F7.2 m/s K RV amplitude
68- 72 F5.2 m/s e_K RV amplitude uncertainty
74- 80 F7.5 --- ecc Eccentricity
82- 88 F7.5 --- e_ecc ? Eccentricity uncertainty
90- 98 F9.4 deg omega Periastron longitude
100-107 F8.4 deg e_omega ? Periastron longitude uncertainty
109-120 F12.6 MJD Tp Time of periastron passage
122-132 F11.6 MJD e_Tp ? Time of periastron passage uncertainty
134-139 F6.4 Msun Mstar Stellar mass
141-146 F6.4 Msun e_Mstar ? Stellar mass uncertainty
148-157 F10.8 au aplan Planet orbit semi-major axis
159-168 F10.8 au e_aplan ? Planet orbit semi-major axis uncertainty
170-174 F5.2 mas Plx Parallax (Gaia DR1 or DR2) (G1)
176-179 F4.2 mas e_Plx ? Parallax uncertainty
181-189 F9.7 mas asini Star orbit projected semi-major axis (asin(i))
191-199 F9.7 mas e_asini ? Star orbit projected semi-major axis
uncertainty
201 A1 --- Transit Transit flag
203 A1 --- Drift RV drift flag
205-208 F4.2 mas epsi1 Astrometric excess noise (G3)
210-212 I3 --- Npts Total number of astrometric measurements
214-215 I2 --- NFoV Number of field-of-view transit
217 I1 --- Dataset Gaia DR1 dataset (G2)
219 A1 --- Dup Duplicate source (G3)
221-222 A2 --- Sample [D ND] Detection or Non-Detection sample
(see text) (4)
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Note (4): Detection or Non-Detection sample as defined in the paper as follows:
D = detection sample
ND = non-detection sample
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Byte-by-byte Description of file: table9.dat
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Bytes Format Units Label Explanations
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1- 15 A15 --- Name Planet name
17 I1 --- Dataset [1/2] Gaia DR1 dataset (G2)
19- 26 F8.3 d Per Orbital period
28- 36 F9.6 jovMass Msini M sin(i)
38- 47 F10.8 mas asini Star orbit projected semi-major axis (asin(i))
49- 54 F6.4 mas epsi1 Astrometric excess noise (G3)
56- 64 F9.6 mas aphot-up Photocenter semi-major axis upper-limit
66- 72 F7.4 deg Ic-low Orbit inclination lower-limit
74- 80 F7.3 jovMass Mc-true Companion true mass upper-limit
82- 88 F7.3 --- deltaV V-band magnitude difference lower-limit (5)
90- 96 F7.5 --- MCMCrate Acceptance rate of the MCMC run
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Note (5): The V-band magnitude difference between the star and the companion,
defined as deltaV = Vplanet - Vstar
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Global notes:
Note (G1): Parallax with no values of uncertainties are taken from the Gaia DR2.
Uncertainties of 10% are assumed.
Note (G2): Gaia DR1 datasets defined in Lindegren+ (2016A&A...595A...4L 2016A&A...595A...4L)
true = primary dataset
false = secondary dataset
Note (G3): see Lindegren et al., 2016A&A...595A...4L 2016A&A...595A...4L, Cat. I/337
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Acknowledgements:
Flavien Kiefer, flavien.kiefer(at)obspm.fr
References:
Lindegren et al., Gaia DR1 2016A&A...595A...4L 2016A&A...595A...4L Cat. I/337
History:
23-Dec-2020: on-line version
29-Sep-2021: table3 corrected (from author)
(End) Flavien Kiefer [LESIA, France], Patricia Vannier [CDS] 27-Nov-2020