J/AJ/155/89 California-Kepler Survey (CKS). IV. Planets (Petigura+, 2018)
The California-Kepler Survey.
IV. Metal-rich stars host a greater diversity of planets.
Petigura E.A., Marcy G.W., Winn J.N., Weiss L.M., Fulton B.J., Howard A.W.,
Sinukoff E., Isaacson H., Morton T.D., Johnson J.A.
<Astron. J., 155, 89 (2018)>
=2018AJ....155...89P 2018AJ....155...89P (SIMBAD/NED BibCode)
ADC_Keywords: Exoplanets ; Models ; Surveys
Keywords: methods: statistical - planets and satellites: formation -
planets and satellites: general - stars: abundances -
stars: fundamental parameters - techniques: spectroscopic
Abstract:
Probing the connection between a star's metallicity and the presence
and properties of any associated planets offers an observational link
between conditions during the epoch of planet formation and mature
planetary systems. We explore this connection by analyzing the
metallicities of Kepler target stars and the subset of stars found to
host transiting planets. After correcting for survey incompleteness,
we measure planet occurrence: the number of planets per 100 stars with
a given metallicity M. Planet occurrence correlates with metallicity
for some, but not all, planet sizes and orbital periods. For warm
super-Earths having P=10-100 days and RP=1.0-1.7 R⊕, planet
occurrence is nearly constant over metallicities spanning -0.4 to
+0.4 dex. We find 20 warm super-Earths per 100 stars, regardless of
metallicity. In contrast, the occurrence of warm sub-Neptunes
(RP=1.7-4.0 R⊕) doubles over that same metallicity interval,
from 20 to 40 planets per 100 stars. We model the distribution of
planets as df∝10βMdM, where β characterizes the
strength of any metallicity correlation. This correlation steepens
with decreasing orbital period and increasing planet size. For warm
super-Earths β=-0.3-0.2+0.2, while for hot Jupiters
β=+3.4-0.8+0.9. High metallicities in protoplanetary disks
may increase the mass of the largest rocky cores or the speed at which
they are assembled, enhancing the production of planets larger than
1.7 R⊕. The association between high metallicity and short-period
planets may reflect disk density profiles that facilitate the inward
migration of solids or higher rates of planet-planet scattering.
Description:
The California-Kepler Survey (CKS) is a large-scale spectroscopic survey
of 1305 Kepler Objects of Interest (KOIs). The sample selection,
spectroscopic observations, and spectroscopic analysis are described
in detail in Petigura et al. (2017, J/AJ/154/107 hereafter Paper I).
Here we provide two tables to supplement Section 5, which treats planet
occurrence as a function of period and radius. Table 8 lists the occurrence
measurements along with upper limits. Table 9 is a sampling of the
occurrence distribution. The integrated occurrence within this domain
is 110.7 planets per 100 stars. We simulated the periods and radii of
a population of 110733 planets in a sample of 100000 Sun-like stars by
drawing 110733 (P, RP) pairs according to their measured occurrence
rates using the Python package pinky. These samples are listed in Table 9.
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table8.dat 56 120 Planet occurrence
table9.dat 21 110733 Simulated planet population
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See also:
J/ApJ/622/1102 : The planet-metallicity correlation. (Fischer+, 2005)
J/AJ/152/187 : Planet occurrence and stellar metallicity for KOIs
(Mulders+, 2016)
J/AJ/154/107 : California-Kepler Survey (CKS). I. 1305 stars
(Petigura+, 2017)
J/AJ/154/108 : California-Kepler Survey (CKS). II. Properties
(Johnson+, 2017)
J/AJ/154/109 : California-Kepler Survey (CKS). III. Planet radii
(Fulton+, 2017)
J/AJ/155/48 : California-Kepler Survey (CKS). V. Masses and radius
(Weiss+, 2018)
Byte-by-byte Description of file: table8.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
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1- 5 F5.2 Rgeo b_Rp [0.5/22.63] Lower limit of planet size bin
7- 11 F5.2 Rgeo B_Rp [0.71/32] Upper limit of planet size bin
13- 18 F6.2 d b_Per [1/177.83] Lower limit of orbital period bin
20- 25 F6.2 d B_Per [1.78/316.23] Upper limit of orbital period bin
27- 28 I2 --- Npl [0/61] Number of planets per bin
30- 33 F4.2 --- Pdet [0/1] Pipeline detectability
35- 40 F6.1 --- Ntrial [0.3/6906.2] Number of effective trials
42 A1 --- l_fcell [<] Limit flag on fcell
43- 46 F4.2 --- fcell [0.02/6.67]? Number of planets per 100 stars
per bin (1)
48- 51 F4.2 --- E_fcell [0.02/2.04]? Upper uncertainty in fcell
53- 56 F4.2 --- e_fcell [0.01/1.52]? Lower uncertainty in fcell
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Note (1): We report 90% upper limits on fcell when there are no planets in
a bin, and we do not report fcell when Pdet<0.25.
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Byte-by-byte Description of file: table9.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 I6 --- Planet [0/110732] Simulated planet identifier (1)
8- 14 F7.3 d Per [0.779/430.329] Simulated planet period (1)
16- 21 F6.3 Rgeo Rp [0.474/34.215] Simulated planet radius (1)
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Note (1): Simulated periods and radii of 110733 planets in a population of
100000 stars based on the measured occurrence rates from Kepler (Section 5).
This table may be used to compute yield simulations for future surveys or
integrated occurrence values over arbitrary bins of orbital period and planet
size.
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History:
From electronic version of the journal
References:
Petigura et al., Paper I 2017AJ....154..107P 2017AJ....154..107P, Cat. J/AJ/154/107
Johnson et al., Paper II 2017AJ....154..108J 2017AJ....154..108J, Cat. J/AJ/154/108
Fulton et al., Paper III 2017AJ....154..109F 2017AJ....154..109F, Cat. J/AJ/154/109
Weiss et al., Paper V 2018AJ....155...48W 2018AJ....155...48W, Cat. J/AJ/155/48
Weiss et al., Paper VI 2018AJ....156..254W 2018AJ....156..254W
Fulton & Petigura., Paper VII 2018AJ....156..264F 2018AJ....156..264F
(End) Prepared by [AAS], Tiphaine Pouvreau [CDS] 18-Oct-2018