J/MNRAS/480/2846 95 RV-discovered single-planet systems (Boisvert+, 2018)
Systematic mischaracterization of exoplanetary system dynamical histories from a
model degeneracy near mean-motion resonance.
Boisvert J.H., Nelson B.E., Steffen J.H.
<Mon. Not. R. Astron. Soc., 480, 2846-2852 (2018)>
=2018MNRAS.480.2846B 2018MNRAS.480.2846B (SIMBAD/NED BibCode)
ADC_Keywords: Stars, double and multiple ; Exoplanets ; Radial velocities ;
Binaries, orbits ; Optical
Keywords: methods: data analysis - techniques: radial velocities -
planetary systems
Abstract:
There is a degeneracy in the radial velocity exoplanet signal between
a single planet on an eccentric orbit and a two-planet system with a
period ratio of 2:1. This degeneracy could lead to misunderstandings
of the dynamical histories of planetary systems as well as
measurements of planetary abundances if the correct architecture is
not established. We constrain the rate of mischaracterization by
analysing a sample of 60 non-transiting, radial velocity systems
orbiting main-sequence stars from the NASA Exoplanet Archive (NASA
Archive) using a new Bayesian model comparison pipeline. We find that
15 systems (25 per cent of our sample) show compelling evidence for
the two-planet case with a confidence level of 95 per cent.
Description:
The extended sample contains 95 systems, which is nearly a quarter of
all RV-discovered single-planet systems.
The parameters for the single eccentric model are: period (P),
velocity semi-amplitude (K), eccentricity (e), longitude of periastron
(ω), and mean anomaly at the time of the earliest RV measurement
[Mo=M(to)]. The parameters for the circular double models are: outer
planet period (Pout), the velocity semi-amplitude for the outer/inner
planets (Kout/Kin), and mean anomaly at the time of the earliest
RV measurement for the outer/inner planets (Mo,out/Mo,in). The
floating circular double model includes the inner planet orbital
period (Pin). Each model also has a linear trend (A) and a velocity
offset (C).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table.dat 490 95 Model parameters with errors for all four models
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Byte-by-byte Description of file: table.dat
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Bytes Format Units Label Explanations
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1- 12 A12 --- Name Star Name
14 I1 --- n_Name [0/1] 0: Main Sequence 1: Non-Main Sequence
16- 23 F8.3 d Per Single Eccentric: Period
25- 31 F7.3 d e_Per Single Eccentric: Period error
33- 40 F8.3 m/s K Single Eccentric: Velocity Semi-Amplitude
42- 47 F6.3 m/s e_K Single Eccentric: Velocity Semi-Amplitude error
49- 53 F5.3 --- e Single Eccentric: Eccentricity
55- 59 F5.3 --- e_e Single Eccentric: Eccentricity error
61- 65 F5.3 rad omega Single Eccentric: Longitude of Periastron
67- 71 F5.3 rad e_omega Single Eccentric: Longitude of Periastron error
73- 77 F5.3 rad M Single Eccentric: Mean Anomaly of Earliest
Observation
79- 83 F5.3 rad e_M Single Eccentric: Mean Anomaly of Earliest
Observation error
85- 90 F6.3 m/s/d A Single Eccentric: linear trend A
92- 96 F5.3 m/s/d e_A Single Eccentric: A error
98-107 F10.3 m/s C Single Eccentric: velocity offset C
109-114 F6.3 m/s e_C Single Eccentric: C error
116-126 E11.6 --- Factora Bayes factor between the 2:1 fixed circular
double model and the single eccentric
model (1)
128-135 F8.3 d PerOuta 2:1 Fixed Circular Double: Outer Period
137-143 F7.3 d e_PerOuta 2:1 Fixed Circular Double: Outer Period error
145-152 F8.3 m/s KOuta 2:1 Fixed Circular Double: Outer Velocity
Semi-Amplitude
154-159 F6.3 m/s e_KOuta 2:1 Fixed Circular Double: Outer Velocity
Semi-Amplitude error
161-165 F5.3 rad MOuta 2:1 Fixed Circular Double: Outer Mean Anomaly
of Earliest Observation
167-171 F5.3 rad e_MOuta 2:1 Fixed Circular Double: Outer Mean Anomaly
of Earliest Observation error
173-179 F7.3 m/s KIna 2:1 Fixed Circular Double: Inner Velocity
Semi-Amplitude
181-186 F6.3 m/s e_KIna 2:1 Fixed Circular Double: Inner Velocity
Semi-Amplitude error
188-192 F5.3 rad MIna 2:1 Fixed Circular Double: Inner Mean Anomaly
of Earliest Observation
194-198 F5.3 rad e_MIna 2:1 Fixed Circular Double: Inner Mean Anomaly
of Earliest Observation error
200-205 F6.3 m/s/d Aa 2:1 Fixed Circular Double: linear trend A
207-211 F5.3 m/s/d e_Aa 2:1 Fixed Circular Double: A error
213-222 F10.3 m/s Ca 2:1 Fixed Circular Double: velocity offset C
224-229 F6.3 m/s e_Ca 2:1 Fixed Circular Double: C error
231-242 E12.8 --- Factorb Bayes factor between the 2.17:1 fixed circular
double model and the single eccentric
model (1)
244-251 F8.3 d PerOutb 2.17:1 Fixed Circular Double: Outer Period
253-260 F8.3 d e_PerOutb 2.17:1 Fixed Circular Double: Outer Period
error
262-269 F8.3 m/s KOutb 2.17:1 Fixed Circular Double: Outer Velocity
Semi-Amplitude
271-276 F6.3 m/s e_KOutb 2.17:1 Fixed Circular Double: Outer Velocity
Semi-Amplitude error
278-282 F5.3 rad MOutb 2.17:1 Fixed Circular Double: Outer Mean
Anomaly of Earliest Observation
284-288 F5.3 rad e_MOutb 2.17:1 Fixed Circular Double: Outer Mean
Anomaly of Earliest Observation error
290-296 F7.3 m/s KInb 2.17:1 Fixed Circular Double: Inner Velocity
Semi-Amplitude
298-303 F6.3 m/s e_KInb 2.17:1 Fixed Circular Double: Inner Velocity
Semi-Amplitude error
305-309 F5.3 rad MInb 2.17:1 Fixed Circular Double: Inner Mean
Anomaly of Earliest Observation
311-315 F5.3 rad e_MInb 2.17:1 Fixed Circular Double: Inner Mean
Anomaly of Earliest Observation error
317-322 F6.3 m/s/d Ab 2.17:1 Fixed Circular Double: linear trend A
324-328 F5.3 m/s/d e_Ab 2.17:1 Fixed Circular Double: A error
330-339 F10.3 m/s Cb 2.17:1 Fixed Circular Double: velocity offset C
341-346 F6.3 m/s e_Cb 2.17:1 Fixed Circular Double: C error
348-361 E14.6 --- Factorc Bayes factor between the floating circular
double model and the single eccentric
model (1)
363-370 F8.3 d PerOutc Floating Circular Double: Outer Period
372-379 F8.3 d e_PerOutc Floating Circular Double: Outer Period error
381-388 F8.3 m/s KOutc Floating Circular Double: Outer Velocity
Semi-Amplitude
390-396 F7.3 m/s e_KOutc Floating Circular Double: Outer Velocity
Semi-Amplitude error
398-402 F5.3 rad MOutc Floating Circular Double: Outer Mean Anomaly
of Earliest Observation
404-408 F5.3 rad e_MOutc Floating Circular Double: Outer Mean Anomaly
of Earliest Observation error
410-417 F8.3 d PerInc Floating Circular Double: Inner Period
419-426 F8.3 d e_PerInc Floating Circular Double: Inner Period error
428-434 F7.3 m/s KInc Floating Circular Double: Inner Velocity
Semi-Amplitude
436-442 F7.3 m/s e_KInc Floating Circular Double: Inner Velocity
Semi-Amplitude error
444-448 F5.3 rad MInc Floating Circular Double: Inner Mean Anomaly
of Earliest Observation
450-454 F5.3 rad e_MInc Floating Circular Double: Inner Mean Anomaly
of Earliest Observation error
456-461 F6.3 m/s/d Ac Floating Circular Double: linear trend A
463-467 F5.3 m/s/d e_Ac Floating Circular Double: A error
469-478 F10.3 m/s Cc Floating Circular Double: velocity offset C
480-485 F6.3 m/s e_Cc Floating Circular Double: C error
487 I1 --- Model [0/1] Preferred Fixed Circular Double Model
(0=2:1 and 1=2.17:1)
489-490 I2 --- Bin Corresponding Percentile Bin (2)
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Note (1): Ratio of the probabilities of the RV data given the circular double
model and the single eccentric model.
Note (2): The bins are 99, 95, 84, 68, 50, and 0.
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 13-May-2022