J/ApJ/767/95 Improved stellar parameters of smallest KIC stars (Dressing+, 2013)
The occurrence rate of small planets around small stars.
Dressing C.D., Charbonneau D.
<Astrophys. J., 767, 95 (2013)>
=2013ApJ...767...95D 2013ApJ...767...95D
ADC_Keywords: Stars, double and multiple ; Stars, diameters ; Planets ;
Abundances, [Fe/H] ; Stars, masses
Keywords: catalogs; methods: data analysis; planetary systems; stars: low-mass;
surveys; techniques: photometric
Abstract:
We use the optical and near-infrared photometry from the Kepler Input
Catalog to provide improved estimates of the stellar characteristics
of the smallest stars in the Kepler target list. We find 3897 dwarfs
with temperatures below 4000K, including 64 planet candidate host
stars orbited by 95 transiting planet candidates. We refit the transit
events in the Kepler light curves for these planet candidates and
combine the revised planet/star radius ratios with our improved
stellar radii to revise the radii of the planet candidates orbiting
the cool target stars. We then compare the number of observed planet
candidates to the number of stars around which such planets could have
been detected in order to estimate the planet occurrence rate around
cool stars. We find that the occurrence rate of 0.5-4R⊕
planets with orbital periods shorter than 50 days is 0.900.030.04
planets per star. The occurrence rate of Earth-size
(0.5-1.4R⊕) planets is constant across the temperature range
of our sample at 0.510.050.06 Earth-size planets per star, but the
occurrence of 1.4-4R⊕ planets decreases significantly at
cooler temperatures. Our sample includes two Earth-size planet
candidates in the habitable zone, allowing us to estimate that the
mean number of Earth-size planets in the habitable zone is
0.150.060.13 planets per cool star. Our 95% confidence lower limit
on the occurrence rate of Earth-size planets in the habitable zones of
cool stars is 0.04 planets per star. With 95% confidence, the nearest
transiting Earth-size planet in the habitable zone of a cool star is
within 21pc. Moreover, the nearest non-transiting planet in the
habitable zone is within 5pc with 95% confidence.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 100 3897 Revised cool star properties
table2.dat 98 95 Revised properties for planet candidates orbiting
small star
table4.dat 49 11 Properties of candidates in or near the
Habitable Zone
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See also:
V/133 : Kepler Input Catalog (Kepler Mission Team, 2009)
J/ApJ/784/45 : Kepler's multiple planet candidates. III. (Rowe+, 2014)
J/ApJS/208/22 : Transit timing variation for 12 planetary pairs (Xie, 2013)
J/ApJS/204/24 : Kepler planetary candidates. III. (Batalha+, 2013)
J/A+A/549/A109 : HARPS XXXI. The M-dwarf sample (Bonfils+, 2013)
J/PASP/124/1279 : Q3 Kepler's combined photometry (Christiansen+, 2012)
J/ApJS/199/30 : KIC stars effective temperature scale (Pinsonneault+, 2012)
J/MNRAS/421/2342 : 4 Kepler systems transit timing obs. (Steffen+, 2012)
J/ApJ/757/112 : Stellar diameters. II. K and M-stars (Boyajian+, 2012)
J/ApJ/753/90 : Stellar param. of K5 & later type Kepler stars (Mann+, 2012)
J/ApJ/750/L37 : Stellar parameters of low-mass KOIs (Muirhead+, 2012)
J/ApJ/750/114 : Kepler TTVs. IV. 4 multiple-planet systems (Fabrycky+, 2012)
J/ApJ/749/15 : The Kepler-20 planetary system (Gautier+, 2012)
J/ApJ/748/93 : K-band spectra for 133 nearby M dwarfs (Rojas-Ayala+, 2012)
J/ApJ/746/36 : RV standard deviation in the M2K survey (Gaidos+, 2012)
J/ApJ/738/170 : False positive Kepler planet candidates (Morton+, 2011)
J/ApJ/736/19 : Kepler planetary candidates. II. (Borucki+, 2011)
J/A+A/529/A75 : Limb-darkening coefficients (Claret+, 2011)
J/AJ/142/112 : KIC photometric calibration (Brown+, 2011)
J/A+A/505/859 : M dwarfs radial velocities (Zechmeister+, 2009)
J/MNRAS/389/585 : Fundamental parameters of M dwarfs (Casagrande+, 2008)
http://archive.stsci.edu/kepler/ : MAST Kepler home page
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 8 I8 --- KIC Kepler Input Catalog ID (V/133)
10- 13 I4 K Teff [3121/4000] Stellar effective temperature
15- 17 I3 K E_Teff Positive error in Teff
19- 21 I3 K e_Teff Negative error in Teff
23- 27 F5.3 Rsun R* [0.1/0.6] Stellar radius
29- 32 F4.2 Rsun E_R* Positive error in R*
34- 37 F4.2 Rsun e_R* Negative error in R*
39- 43 F5.3 Msun M* [0.09/0.7] Stellar mass
45- 48 F4.2 Msun E_M* Positive error in M*
50- 53 F4.2 Msun e_M* Negative error in M*
55- 59 F5.3 [cm/s2] logg [4.6/5.4] Log surface gravity
61- 64 F4.2 [cm/s2] E_logg Positive error in logg
66- 69 F4.2 [cm/s2] e_logg Negative error in logg
71- 75 F5.2 [Sun] Fe/H [-2.5/0.3] Stellar metallicity
77- 80 F4.2 [Sun] E_Fe/H Positive error in Fe/H
82- 85 F4.2 [Sun] e_Fe/H Negative error in Fe/H
87- 92 F6.1 pc Dist [8/1099] Distance
94- 96 I3 pc E_Dist Positive error in Dist
98-100 I3 pc e_Dist Negative error in Dist
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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- 7 F7.2 --- KOI Kepler Object of Interest
9 A1 --- n_KOI Note on planet (1)
11- 18 I8 --- KIC Kepler identifier (V/133)
20- 25 F6.3 d t0 [0/44] Transit ephemeris folded to planet
orbital period (between 0 and Per)
27- 32 F6.3 d Per [0.5/87] Planet orbital period
34- 40 F7.3 --- a/r* [1.7/158] Planet semimajor axis/stellar radius (2)
42- 46 F5.3 --- rp/r* [0.01/0.5] Planet radius/stellar radius
48- 50 F3.1 --- b [0.3/1.3] Impact parameter
52- 56 F5.2 Rgeo Rp [0.4/18] Planet radius in Earth radii
58- 61 F4.2 Rgeo E_Rp Positive error on Rp
63- 66 F4.2 Rgeo e_Rp Negative error on Rp
68- 73 F6.2 Earth Fp [0.3/551] Flux received by planet
(relative to Earth)
75- 80 F6.2 Earth E_Fp Positive error on Fp
82- 87 F6.2 Earth e_Fp Negative error on Fp
89- 92 I4 K Teff [3304/3994] Stellar effective temperature
94- 98 F5.3 Rsun R* [0.2/0.6] Stellar radius
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Note (1): Flag as follows:
b = Kepler-49b (Steffen et al. 2013MNRAS.428.1077S 2013MNRAS.428.1077S;
Xie 2012, 1208.3312)
c = Kepler-49c (Steffen et al. 2013MNRAS.428.1077S 2013MNRAS.428.1077S;
Xie 2012, 1208.3312)
d = Kepler-26b (Steffen et al. 2012, J/MNRAS/421/2342);
e = Kepler-26c (Steffen et al. 2012, J/MNRAS/421/2342);
f = Confirmed by Johnson et al. (2012AJ....143..111J 2012AJ....143..111J);
g = Transits noted as "v"-shaped by Batalha et al. 2013 (J/ApJS/204/24)
h = Kepler-54b (Steffen et al. 2013MNRAS.428.1077S 2013MNRAS.428.1077S);
i = Kepler-54c (Steffen et al. 2013MNRAS.428.1077S 2013MNRAS.428.1077S);
j = Confirmed by Xie 2012 (1208.3312);
k = Confirmed by Xie 2012 (1208.3312);
l = Kepler-32b (Fabrycky et al. 2012, Cat. J/ApJ/750/114);
m = Kepler-32c (Fabrycky et al. 2012, Cat. J/ApJ/750/114);
Note (2): The ratio estimated from the fit to the light curve. We compute
the geometric probability of transit using the semimajor axis
determined from the planet orbital period and the host star mass
listed in Table 1.
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 7 F7.2 --- KOI Kepler Object of Interest identifier
9 A1 --- n_KOI [i] i: in the Habitable Zone
11- 18 I8 --- KIC Kepler number
20- 23 I4 K Teff [3414/3853] Stellar effective temperature
25- 28 F4.2 Rsun R* [0.2/0.5] Stellar radius
30- 33 F4.1 [-] [Fe/H] [-0.5/-0.1] Stellar metallicity
35- 39 F5.2 d Per [18.4/86.9] Planet orbital period
41- 44 F4.2 Rgeo Rp [0.9/2.4] Planet radius (in Earth radius)
46- 49 F4.2 Earth Fp [0.3/2] Flux received by planet (compared to
flux received by Earth)
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 19-Nov-2014