J/AJ/169/90 Mandel-Agol & dynamical parameters of KOI planets (Ofir+, 2025)
Planetary mass determinations from a simplified photodynamical model:
Application to the complete Kepler dataset.
Ofir A., Yoffe G., Aharonson O.
<Astron. J., 169, 90 (2025)>
=2025AJ....169...90O 2025AJ....169...90O
ADC_Keywords: Exoplanets; Stars, diameters; Stars, masses; Models; Optical
Keywords: Exoplanet astronomy ; Exoplanet systems ; Time series analysis
Abstract:
We use PyDynamicaLC, a model using the least number of--and the least
correlated--degrees of freedom needed to derive a photodynamical model,
to describe some of the smallest--and
lowest-transit-timing-variation-amplitude--of the Kepler planets. We
successfully analyze 64 systems containing 218 planets, for 88 of
which we were able to determine significant masses (to better than
3σ). We demonstrate consistency with literature results over
2 orders of magnitude in mass, and for the planets that already had
literature mass estimations, we were able to reduce the relative mass
error by ∼22% (median value). Of the planets with determined masses,
23 are new mass determinations, with no previous significant
literature values, including a planet smaller and lighter than Earth
(KOI-1977.02/Kepler-345 b). These results demonstrate the power of
photodynamical modeling with the appropriately chosen degrees of
freedom. This will become increasingly more important as smaller
planets are detected, especially as the TESS mission gathers ever
longer baseline light curves and for the analysis of the future PLATO
mission data.
Description:
Our initial sample is the 440 KOIs from 373 systems that have
high-confidence TTV (99%) based on bootstrapping analysis, as
presented in Ofir+2018 (J/ApJS/234/9). Of these, 163 multitransiting
systems were selected for this study, since we aim to model the
interaction among known planets. TTVs in singly transiting systems are
likely caused by unseen companions, so they were not considered here.
Several systems were manually removed due to difficulties in the
preprocessing stage, for example, due to orbiting highly active stars
with background variability or variable apparent depth. We also note
that in this sample, we do not analyze high-amplitude TTVs (amplitudes
comparable to the transit duration or longer), bringing down the
number of host stars in our sample to 45.
The final Kepler DR25 data were obtained from the NASA Exoplanet
Archive (NExScI) database.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 57 45 Stellar parameters used in this work
table2.dat 116 145 Planetary Mandel-Agol parameters used in this work
table3.dat 160 187 Dynamical parameters found in this work
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See also:
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
I/355 : Gaia DR3 Part 1. Main source (Gaia Collaboration, 2022)
V/133 : Kepler Input Catalog (Kepler Mission Team, 2009)
J/ApJ/728/117 : Kepler planetary candidates. I. (Borucki+, 2011)
J/ApJ/736/19 : Kepler planetary candidates. II. (Borucki+, 2011)
J/A+A/555/A58 : New Kepler planetary candidates (Ofir+, 2013)
J/ApJS/208/22 : Transit timing variation for 12 planetary pairs (Xie, 2013)
J/ApJ/787/80 : 139 Kepler planets transit time variations (Hadden+, 2014)
J/ApJ/795/167 : Transits of PH3 b, c, & d through Jan, 2019 (Schmitt+, 2014)
J/ApJS/210/25 : Transit timing var. for 15 planetary pairs. II. (Xie, 2014)
J/A+A/573/A124 : Kepler-117 (KOI-209) transit-timing variations (Bruno+, 2015)
J/ApJS/224/12 : Kepler planetary candidates. VII. 48-month (Coughlin+, 2016)
J/ApJS/225/9 : Kepler TTVs. IX. The full long-cadence data set (Holczer+, 2016)
J/AJ/152/105 : Kepler-80 transit timing observations (MacDonald+, 2016)
J/A+A/587/A64 : Physical properties of giant exoplanets (Santerne+, 2016)
J/ApJ/839/94 : Abundances of solar twins from Keck/HIRES (Bedell+, 2017)
J/AJ/154/5 : Transit timing variations of 145 Kepler planets (Hadden+, 2017)
J/MNRAS/465/2634 : Kepler and K2 best candidates for planets (Armstrong+, 2017)
J/ApJ/866/99 : Revised radii: KIC stars & planets with GaiaDR2 (Berger+, 2018)
J/AJ/156/264 : California-Kepler Survey. VII. Planet rad. gap (Fulton+, 2018)
J/ApJS/234/9 : A spectral approach to transit timing variations (Ofir+, 2018)
J/ApJS/235/38 : Kepler planetary cand. VIII. DR25 reliability (Thompson+, 2018)
J/A+A/628/A108 : Photometry of Kepler-82b and c transits (Freudenthal+, 2019)
J/AJ/159/57 : HST spect. LCs of Kepler 51b & 51d (Libby-Roberts+, 2020)
J/AJ/161/246 : Transit time variations for 12 exoplanets (Jontof-Hutter+, 2021)
J/AJ/163/91 : Param. & dynamic solutions of Kepler planets (Judkovsky+, 2022)
http://exoplanetarchive.ipac.caltech.edu/ : NASA Exoplanet Archive (NExSci)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- KOI [94/2038] Kepler Object of Interest identifier
6- 10 F5.3 Msun Mass [0.13/1.34] Stellar mass
12- 16 F5.3 Msun E_Mass [9e-3/0.14] Positive uncertainty in Mass
18- 22 F5.3 Msun e_Mass [0.01/0.14] Negative uncertainty in Mass
24- 28 F5.3 Rsun Rad [0.17/1.85] Stellar radius
30- 35 F6.4 Rsun E_Rad [3e-3/0.14] Positive uncertainty in Radius
37- 42 F6.4 Rsun e_Rad [4e-3/0.14] Negative uncertainty in Radius
44- 48 F5.3 --- LD1 [0.26/0.69] First limb darkening coefficient (1)
50- 54 F5.3 --- LD2 [0.06/0.44] Second limb darkening coefficient (1)
56- 57 I2 --- Ref [1/3] References (2)
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Note (1): Used in the quadratic limb-darkening law in the light curve fit.
Note (2): References for Mass and Rad as follows:
1 = Fulton+2018 (J/AJ/156/264)
2 = NASA Exoplanet Archive (NExSci) Table
3 = NExSci Table (Mass) and Berger+2018 (J/ApJ/866/99) (Rad).
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- KOI [94/2038] Kepler Object of Interest identifier of
the host star (Column added by CDS)
6- 12 F7.2 --- KOIp [94.01/2038.04] KOI planet identifier
14- 26 F13.9 d Per [0.45/330.1] Mean orbital period
28- 38 F11.9 d e_Per [8.4e-8/7e-3] Uncertainty in Per
40- 49 F10.6 d Tmid [128/826] Mean Barycentric Julian Date of
mid-eclipse (BJD-2454833)
51- 58 F8.6 d e_Tmid [2e-5/0.03] Uncertainty in Tmid
60- 67 F8.4 --- a/Rs [3.3/449] Normalized semi-major axis (1)
69- 76 F8.4 --- e_a/Rs [4e-3/184] Uncertainty in a/R
78- 85 F8.6 --- b/Rs [0/1] Normalized impact parameter (1)
87- 94 F8.6 --- e_b/Rs [5.8e-5/0.7] Uncertainty in b/R
96- 105 F10.8 --- r/Rs [4e-3/0.11] Normalized radius (1)
107- 116 F10.8 --- e_r/Rs [8.4e-7/0.02] Uncertainty in r/R
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Note (1): All normalized to star radius Rs.
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 I4 --- KOI [94/2038] Kepler Object of Interest identifier of
the host star (Column added by CDS)
6- 12 F7.2 --- KOIp [94.01/2038.04] KOI planet identifier
14 I1 --- SolN [1/2] Solution number (1)
16- 23 F8.3 --- mu [0.05/2650] Normalized µ parameter * 1e6
25- 33 F9.3 --- E_mu [0.04/7027] Positive uncertainty in mu
35- 43 F9.3 --- e_mu [0.01/2630] Negative uncertainty in mu
45- 56 F12.6 Mgeo Mass [0.01/12652] Planetary mass
58- 66 F9.4 Mgeo E_Mass [0/100] Positive uncertainty in Mass (2)
68- 76 F9.4 Mgeo e_Mass [0/117] Negative uncertainty in Mass (2)
78- 84 F7.4 --- Dex [-0.08/0.09] Difference in X eccentricity vector
component (3)
86- 92 F7.4 --- E_Dex [0.001/0.06] Positive uncertainty in Dex
94- 100 F7.4 --- e_Dex [0.001/0.06] Negative uncertainty in Dex
102- 108 F7.4 --- Dey [-0.09/0.07] Difference in Y eccentricity vector
component (3)
110- 116 F7.4 --- E_Dey [0.001/0.06] Positive uncertainty in Dey
118- 124 F7.4 --- e_Dey [0.001/0.06] Negative uncertainty in Dey
126- 135 F10.5 g/cm3 rho [7e-4/2331] Planetary density
137- 147 F11.5 g/cm3 E_rho [5e-4/6182] Positive uncertainty in rho
149- 160 F12.5 g/cm3 e_rho [2e-4/2316] Negative uncertainty in rho
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Note (1): This column allows differentiating between different solutions of
the same system (as described in the text, there are up to two
solutions for all systems).
Note (2): In all cases µ states the usual value and 1σ uncertainties,
however, the mass column is slightly different: for significant
detections Mass>3e_Mass the mass and 1σ uncertainties are
given, while for masses that are not statistically significant the
value given is the 3σ upper limit, and the uncertainties are
set to zero.
Note (3): Dex and Dey for each planet are the differences in the eccentricity
vector components between each planet and the one interior to it in
the system. The Dex and Dey values for the innermost planet in each
system are understood to be the magnitude of the same eccentricity
components for that innermost planet.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Robin Leichtnam [CDS] 26-Nov-2025