J/AJ/159/211 Exoplanet parameters from Kepler and K2 (Cloutier+, 2020)
Evolution of the radius valley around low-mass stars from Kepler and K2.
Cloutier R., Menou K.
<Astron. J., 159, 211 (2020)>
=2020AJ....159..211C 2020AJ....159..211C
ADC_Keywords: Exoplanets; Stars, dwarfs
Keywords: Transits ; Radial velocity ; Exoplanets ; Low mass stars ;
Exoplanet formation ; Exoplanet evolution ; Astrostatistics
Abstract:
We present calculations of the occurrence rate of small close-in
planets around low-mass dwarf stars using the known planet populations
from the Kepler and K2 missions. Applying completeness corrections
clearly reveals the radius valley in the maximum a posteriori
occurrence rates as a function of orbital separation and planet
radius. We measure the slope of the valley to be
rp,valley∝F-0.060±0.025, which bears the opposite sign
from that measured around Sun-like stars, thus suggesting that
thermally driven atmospheric mass loss may not dominate the evolution
of planets in the low stellar mass regime or that we are witnessing
the emergence of a separate channel of planet formation. The latter
notion is supported by the relative occurrence of rocky to non-rocky
planets increasing from 0.5±0.1 around mid-K dwarfs to 8.5±4.6
around mid-M dwarfs. Furthermore, the center of the radius valley at
1.54±0.16R{earth} is shown to shift to smaller sizes with
decreasing stellar mass, in agreement with physical models of
photoevaporation, core-powered mass loss, and gas-poor formation.
Although current measurements are insufficient to robustly identify
the dominant formation pathway of the radius valley, such inferences
may be obtained by the Transiting Exoplanet Survey Satellite with
O(85000) mid-to-late M dwarfs observed with 2minutes cadence. The
measurements presented herein also precisely designate the subset of
planetary orbital periods and radii that should be targeted in radial
velocity surveys to resolve the rocky to non-rocky transition around
low-mass stars.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 65 275 Kepler confirmed planet parameters
table2.dat 65 53 K2 confirmed planet parameters
table3.dat 87 20 Planets with ≥3σ bulk density measurements
around low-mass stars
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See also:
V/133 : Kepler Input Catalog (Kepler Mission Team, 2009)
IV/34 : K2 Ecliptic Plane Input Catalog (EPIC) (Huber+, 2017)
I/347 : Distances to 1.33 billion stars in Gaia DR2 (Bailer-Jones+, 2018)
IV/38 : TESS Input Catalog - v8.0 (TIC-8) (Stassun+, 2019)
J/AJ/106/773 : Mass-luminosity relation (Henry+, 1993)
J/ApJ/757/112 : Stellar diameters. II. K and M-stars (Boyajian+, 2012)
J/A+A/546/A14 : Limb-darkening for CoRoT, Kepler, Spitzer (Claret+, 2012)
J/MNRAS/422/2024 : X-ray-age relation and exoplanet evaporation (Jackson+,2012)
J/A+A/549/A109 : HARPS XXXI. The M-dwarf sample (Bonfils+, 2013)
J/ApJ/767/95 : Stellar parameters of smallest KIC stars (Dressing+, 2013)
J/ApJ/791/10 : Radius distribution planets around cool stars (Morton+,2014)
J/AJ/148/64 : HAZMAT. I. FUV & NUV emission early M stars (Shkolnik+,2014)
J/ApJ/809/8 : Terres. planet occurrence rates for KOI stars (Burke+, 2015)
J/ApJ/810/95 : Kepler pipeline S/N studies. II. 2011 (Christiansen+, 2015)
J/ApJ/807/45 : Habitable planets orbiting M dwarfs (Dressing+, 2015)
J/ApJ/804/64 : Empirical and model parameters of 183 M dwarfs (Mann+, 2015)
J/ApJ/809/25 : Stellar & planet properties K2 candidates (Montet+, 2015)
J/ApJ/814/130 : Planet occurrence rates calculated for KOIs (Mulders+,2015)
J/ApJ/828/99 : Kepler pipeline transit recovery. III. (Christiansen+, 2016)
J/ApJS/226/7 : Planet candidates using K2's 1st yr (Crossfield+, 2016)
J/MNRAS/457/2877 : Kepler M dwarf stars revised properties (Gaidos+, 2016)
J/AJ/152/105 : Kepler-80 transit timing observations (MacDonald+, 2016)
J/ApJ/834/17 : Mass & radius of planets, moons, low mass stars (Chen+,2017)
J/AJ/154/207 : K2 planet. systems orbiting low-mass stars (Dressing+, 2017)
J/ApJ/844/102 : KIC star plxs from asteroseismology vs Gaia (Huber+, 2017)
J/ApJS/229/30 : Stellar properties of Q1-17 Kepler targets (Mathur+, 2017)
J/ApJS/239/2 : Simulated exoplanets from TESS targets (Barclay+, 2018)
J/ApJ/866/99 : Radii of KIC stars & planets using Gaia DR2 (Berger+, 2018)
J/MNRAS/479/5491 : Absolute parameters of 509 main-sequence stars (Eker+, 2018)
J/AJ/156/264 : California-Kepler Survey. VII. Planet radius (Fulton+, 2018)
J/AJ/156/277 : 60 planets from K2 campaigns 5-8 (Livingston+, 2018)
J/AJ/155/136 : Planets orbiting bright stars in K2 campaigns (Mayo+, 2018)
J/AJ/158/81 : Low-mass stars from the first 2 TESS sectors (Cloutier,2019)
J/AJ/158/75 : M dwarfs planet occurrence rates (Hardegree-Ullman+, 2019)
J/ApJS/244/11 : Planet candidates and EBs in K2 campaigns 0-8 (Kruse+, 2019)
J/AJ/157/216 : Stars multipl. rate of M dwarfs within 25 pc (Winters+,2019)
J/ApJS/247/28 : K2 stars from Gaia & LAMOST (Hardegree-Ullman+, 2020)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- KIC Kepler Input Catalog (KIC; V/133) star identifier
11- 23 A13 --- ID Planet identifier
25- 32 F8.5 d Per [0.58/92.8] Orbital period
34- 38 F5.1 Earth Flux [0.4/950] Flux relative to the Earth
40- 44 F5.1 Earth E_Flux [0/171] Upper limit in Flux
46- 50 F5.1 Earth e_Flux [0/145] Lower limit in Flux
52- 55 F4.2 Rgeo Rp [0.49/3.48] Planetary radius
57- 60 F4.2 Rgeo E_Rp [0.03/0.76] Upper limit in Rp
62- 65 F4.2 Rgeo e_Rp [0.03/0.62] Lower limit in Rp
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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- 9 A9 --- EPIC Ecliptic Plane Input Catalog (EPIC; IV/34)
star identifier
11- 23 A13 --- ID Planet identifier
25- 32 F8.5 d Per [0.68/44.6] Orbital period
34- 38 F5.1 Earth Flux [1.1/870] Flux relative to the Earth
40- 44 F5.1 Earth E_Flux [0.1/1679] Upper limit in Flux
46- 50 F5.1 Earth e_Flux [0.1/153] Lower limit in Flux
52- 55 F4.2 Rgeo Rp [0.92/4.51] Planetary radius
57- 60 F4.2 Rgeo E_Rp [0.09/0.6] Upper limit in Rp
62- 65 F4.2 Rgeo e_Rp [0.08/0.57] Lower limit in Rp
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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- 11 A11 --- ID Planet identifier
13- 20 F8.5 d Per [0.76/33] Orbital period
22- 26 F5.1 Earth Flux [0.5/326.9] Flux relative to the Earth
28- 31 F4.1 Earth e_Flux [0/21] Error on Flux
33- 36 F4.2 Rgeo Rp [1.13/2.85] Planetary radius
38- 41 F4.2 Rgeo e_Rp [0.02/0.2] Error on Rp
43- 46 F4.2 Mgeo Mp [1.66/8.63] Planetary mass
48- 51 F4.2 Mgeo e_Mp [0.18/1.65] Error on Mp
53- 57 F5.2 g/cm3 rho [1.5/10.5] Planetary bulk density
59- 63 F5.2 g/cm3 e_rho [-2.2/-0.3] Negative error on rho
65- 68 F4.2 g/cm3 E_rho [0.34/2.6] Positive error on rho
70- 81 A12 --- Comp Disposition; Rocky, Intermediate or Gaseous
83- 87 A5 --- Ref Reference(s) (1)
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Note (1): References as follows:
1 = Luque+, 2019, J/A+A/628/A39
2 = Dittmann+, 2017, J/AJ/154/142
3 = Bonfils+, 2018, J/A+A/618/A142
4 = Harpsoe+, 2013, J/A+A/549/A10
5 = Rice+, 2019MNRAS.484.3731R 2019MNRAS.484.3731R
6 = Gillon+, 2017NatAs...1E..56G 2017NatAs...1E..56G
7 = Benneke+, 2017ApJ...834..187B 2017ApJ...834..187B
8 = Cloutier+, 2019, J/A+A/621/A49
9 = Hamann+, 2019, J/AJ/158/133
10 = MacDonald+, 2016, J/AJ/152/105
11 = Kostov+, 2019AJ....158...32K 2019AJ....158...32K
12 = Cloutier+, 2019, J/A+A/629/A111
13 = Astudillo-Defru+, 2020, J/A+A/636/A58
14 = Dittmann+, 2017Natur.544..333D 2017Natur.544..333D
15 = Ment+, 2019AJ....157...32M 2019AJ....157...32M
16 = Cloutier+, 2020arXiv200301136C 2020arXiv200301136C
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History:
From electronic version of the journal
(End) Prepared by [AAS], Coralie Fix [CDS], 02-Jun-2020