J/ApJS/210/20 Small Kepler planets radial velocities (Marcy+, 2014)
Masses, radii, and orbits of small Kepler planets: the transition from gaseous
to rocky planets.
Marcy G.W., Isaacson H., Howard A.W., Rowe J.F., Jenkins J.M., Bryson S.T.,
Latham D.W., Howell S.B., Gautier Iii T.N., Batalha N.M., Rogers L.,
Ciardi D., Fischer D.A., Gilliland R.L., Kjeldsen H.,
Christensen-Dalsgaard J., Huber D., Chaplin W.J., Basu S., Buchhave L.A.,
Quinn S.N., Borucki W.J., Koch D.G., Hunter R., Caldwell D.A.,
Van Cleve J., Kolbl R., Weiss L.M., Petigura E., Seager S., Morton T.,
Johnson J.A., Ballard S., Burke C., Cochran W.D., Endl M., Macqueen P.,
Everett M.E., Lissauer J.J., Ford E.B., Torres G., Fressin F., Brown T.M.,
Steffen J.H., Charbonneau D., Basri G.S., Sasselov D.D., Winn J.,
Sanchis-Ojeda R., Christiansen J., Adams E., Henze C., Dupree A.,
Fabrycky D.C., Fortney J.J., Tarter J., Holman M.J., Tenenbaum P.,
Shporer A., Lucas P.W., Welsh W.F., Orosz J.A., Bedding T.R.,
Campante T.L., Davies G.R., Elsworth Y., Handberg R., Hekker S., Karoff C.,
Kawaler S.D., Lund M.N., Lundkvist M., Metcalfe T.S., Miglio A.,
Aguirre V.S., Stello D., White T.R., Boss A., Devore E., Gould A., Prsa A.,
Agol E., Barclay T., Coughlin J., Brugamyer E., Mullally F., Quintana E.V.,
Still M., Thompson S.E., Morrison D., Twicken J.D., Desert J.-M.,
Carter J., Crepp J.R., Hebrard G., Santerne A., Moutou C., Sobeck C.,
Hudgins D., Haas M.R., Robertson P., Lillo-Box J., Barrado D.
<Astrophys. J. Suppl. Ser., 210, 20 (2014)>
=2014ApJS..210...20M 2014ApJS..210...20M
ADC_Keywords: Planets ; Radial velocities ; Stars, masses ; Stars, diameters
Keywords: planetary systems; planets and satellites: detection;
stars: individual (Kepler-25,Kepler-37,Kepler-48,Kepler-68,Kepler-93,
Kepler-94,Kepler-95,Kepler-96,Kepler-97,Kepler-98,Kepler-99,
Kepler-100,Kepler-102,Kepler-103,Kepler-106,Kepler-109,Kepler-113,
Kepler-131,Kepler-406,Kepler-407,Kepler-409;
techniques: photometric; techniques: radial velocities
Abstract:
We report on the masses, sizes, and orbits of the planets orbiting 22
Kepler stars. There are 49 planet candidates around these stars,
including 42 detected through transits and 7 revealed by precise
Doppler measurements of the host stars. Based on an analysis of the
Kepler brightness measurements, along with high-resolution imaging and
spectroscopy, Doppler spectroscopy, and (for 11 stars)
asteroseismology, we establish low false-positive probabilities (FPPs)
for all of the transiting planets (41 of 42 have an FPP under 1%), and
we constrain their sizes and masses. Most of the transiting planets
are smaller than three times the size of Earth. For 16 planets, the
Doppler signal was securely detected, providing a direct measurement
of the planet's mass. For the other 26 planets we provide either
marginal mass measurements or upper limits to their masses and
densities; in many cases we can rule out a rocky composition. We
identify six planets with densities above 5 g/cm3, suggesting a mostly
rocky interior for them. Indeed, the only planets that are compatible
with a purely rocky composition are smaller than ∼2 R⊕. Larger
planets evidently contain a larger fraction of low-density material
(H, He, and H2O).
Description:
Here we report measured masses, radii, and densities (or upper limits
on those values) for 42 transiting planet candidates contained within
22 bright Kepler Objects of Interest (KOIs) from Batalha et al.
(2013, Cat. J/ApJS/204/24). We carried out multiple Doppler-shift
measurements of the host stars using the Keck 1 telescope. From the
spectroscopy and Doppler measurements, we compute self-consistent
measurements of stellar and planet radii, employing either stellar
structure models or asteroseismology measurements from the Kepler
photometry. We also search for (and report) 7 additional
non-transiting planets revealed by the precise radial velocities
(RVs), for a total of 49 planets.
We carried out "reconnaissance" high-resolution spectroscopy on ∼1000
KOIs with spectral resolution, R∼50000, and S/N=20-100 per pixel. The
dual goals were searching for false positives and refining the stellar
parameters. We obtained one or two such reconnaissance spectra using
one of four facilities: the McDonald Observatory 2.7m, the Tillinghast
1.5m on Mt. Hopkins, the Lick Observatory 3m, and the 2.6m Nordic
Optical Telescope.
Speckle imaging of each of the selected 22 KOIs was obtained using the
two-color DSSI speckle camera at the WIYN 3.5m telescope on Kitt Peak.
All 22 KOIs were observed with the Keck NIRC2-AO system.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 116 22 Stellar parameters
table2.dat 149 49 Planet properties and orbital parameters
table4.dat 43 677 Radial velocities
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See also:
V/133 : Kepler Input Catalog (Kepler Mission Team, 2009)
J/ApJS/208/22 : Transit timing variation for 12 planetary pairs (Xie, 2013)
J/ApJS/204/24 : Kepler planetary candidates. III. (Batalha+, 2013)
J/ApJ/750/L37 : Stellar parameters of low-mass KOIs (Muirhead+, 2012)
J/other/Nat/486.375 : Stellar parameters of KOI stars (Buchhave+, 2012)
J/MNRAS/423/122 : Abundances of 93 solar-type Kepler targets (Bruntt+, 2012)
J/MNRAS/421/2342 : 4 Kepler systems transit timing obs. (Steffen+, 2012)
J/A+A/546/A10 : Multiplicity in transiting planet-host stars (Lillo-Box+, 2012)
J/AJ/144/42 : Infrared photometry of 90 KOIs (Adams+, 2012)
J/AJ/142/19 : Speckle observations of KOI (Howell+, 2011)
J/ApJ/742/L19 : Physics of Kepler hot rocky planetary cand. (Miguel+, 2011)
J/ApJ/738/170 : False positive Kepler planet candidates (Morton+, 2011)
J/ApJ/733/68 : Exoplanet masses derived from RVs (Brown+, 2011)
J/MNRAS/412/1210 : Kepler asteroseismic targets (Molenda-Zakowicz+, 2011)
J/ApJ/736/19 : Kepler planetary candidates. II. (Borucki+, 2011)
J/ApJS/197/8 : Kepler's cand. multiple transiting planets (Lissauer+, 2011)
J/ApJ/725/875 : Chromospheric activity for CPS stars (Isaacson+, 2010)
J/other/Sci/330.653 : Detected planets in the Eta-Earth Survey (Howard+, 2010)
J/A+A/506/303 : CoRoT-7 radial velocities (Queloz+, 2009)
J/A+A/482/L17 : CoRoT space mission. I. (Barge+, 2008)
J/ApJS/159/141 : Spectroscopic properties of cool stars. I. (Valenti+, 2005)
J/ApJ/622/1102 : The planet-metallicity correlation. (Fischer+, 2005)
http://exoplanetarchive.ipac.caltech.edu/ : NASA exoplanet archive
http://stdatu.stsci.edu/kepler/ : MAST Kepler home page
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 --- Kepler Kepler number if any
12- 15 I4 --- KOI Kepler object of interest number
(<KOI-NNNN> in Simbad)
17- 24 I8 --- KIC Kepler input catalog number
26- 27 I2 h RAh Hour of right ascension (J2000)
29- 30 I2 min RAm Minute of right ascension (J2000)
32- 35 F4.1 s RAs Second of right ascension (J2000)
37 A1 --- DE- Sign of declination (J2000)
38- 39 I2 deg DEd Degree of declination (J2000)
41- 42 I2 arcmin DEm Arcminute of declination (J2000)
44- 45 I2 arcsec DEs Arcsecond of declination (J2000)
47- 50 I4 K Teff [4725/6270] Effective temperature
52- 54 I3 K e_Teff [73/129] Teff uncertainty
56- 60 F5.3 [cm/s2] logg [4.1/4.7] Stellar surface gravity
62- 65 F4.2 [cm/s2] e_logg [0.02/0.2] logg uncertainty
67- 71 F5.2 [Sun] [Fe/H] [-0.4/0.4] [Fe/H] abundance
73- 76 F4.2 [Sun] e_[Fe/H] [0.07/0.2] [Fe/H] uncertainty
78- 81 F4.2 Msun M* [0.7/1.2] Stellar mass
83- 86 F4.2 Msun e_M* [0.05/0.08] M* uncertainty
88- 91 F4.2 Rsun R* [0.6/1.5] Stellar radius
93- 96 F4.2 Rsun e_R* [0.02/0.2] R* uncertainty
98-100 F3.1 km/s vsini [0.3/9.5] Rotational velocity
102-106 F5.2 mag Kpmag [8.7/13.5] Kepler magnitude
108-112 F5.2 Gyr Age [1.4/11] Age
114-116 A3 --- Src MCMC+ source, AS or SME (1)
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Note (1): Markov Chain Monte Carlo (MCMC) code as follows:
AS = Asteroseismology provided the input stellar values of Teff and logg to
the MCMC analysis of the planet-transit model that further constrained
stellar parameters. LTE spectrum synthesis, SME, yielded initial
measurements of Teff, logg, and metallicity, used as input values and
priors for the asteroseismology analysis.
SME = the SME code performed LTE spectrum analysis to yield Teff, logg, and
metallicity, used as input to the MCMC analysis of the planet transit
model. Iteration with Yonsei-Yale stellar models constrained all stellar
values.
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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- 11 A11 --- Kepler Kepler number if any
13- 19 F7.2 --- KOI KOI planet identification
(<KOI-NNNN.NN> in Simbad)
21 A1 --- n_KOI Individual notes (1)
23 A1 --- l_Per Limit flag on Per
25- 35 F11.6 d Per [0.6/3000] Orbital period determined using
only Kepler photometry
37- 39 I3 d e_Per [2/500]? Period uncertainty
41- 44 F4.2 Rgeo Rad [0.3/5.2]? Planet radius (2)
46- 49 F4.2 Rgeo e_Rad [0.02/0.4]? Radius uncertainty (2)
51 A1 --- l_Mpk Limit flag on Mpk
53- 59 F7.2 Mgeo Mpk [-6.39/4000] Planet mass (peak) (3)
61- 67 F7.2 Mgeo e_Mpk [1.2/2000]? Mpk uncertainty
69- 75 F7.2 Mgeo Mass [3/8000]? Planet mass (95%) (4)
77- 82 F6.2 g/cm3 Dp [-44.3/548.8]? Planet density (5)
84- 89 F6.2 g/cm3 e_Dp [0.2/700]? Dp uncertainty
91 A1 --- l_K Limit flag on K
93- 98 F6.2 m/s K [-2.9/262.7] RV amplitude (6)
100-104 F5.2 m/s e_K [0.5/20]? K uncertainty
106-109 F4.2 g/cm3 D* [0.4/2.9]? Stellar density
111-114 F4.2 g/cm3 e_D* [0/0.4]? D* uncertainty
116-119 F4.2 --- b ? Impact parameter of the transit
121-124 F4.2 --- e_b ? b uncertainty
126-133 F8.6 --- Rp/R* [0.003/0.05]? Ratio of planetary radius to
stellar radius
135-143 F9.5 d MidE ? Mid-transit Epoch (BJD-2454900)
145-149 F5.3 --- chi2 [0.8/1.5]? Reduced χ2
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Note (1): Flag as follows:
g = Long term variation in RVs indicates a long period orbiting object,
which may not be a planet (Marcy et al. 2001).
h = A floating orbital eccentricity was allowed in the model for the outer,
non-transiting planet, as indicated by apparent non-sinusoidal long-term
variation in the RVs, for Kepler-94, Kepler-25, and Kepler-68. The
best-fit eccentricities are 0.38±0.05, 0.18±0.10, and 0.10±0.04,
respectively. See notes in Section 7 on the individual KOIs for more
information.
i = For Kepler-113, the RV residuals to the fit to the two transiting planets
indicate the presence of a third, non-transiting planet. The highest
periodogram peak is at a period, P=1.065 days. But peaks appear at
aliases, namely at 16 days, 0.984 days, and 0.515 days. We are not able
to determine which among this family of alias periods is the real period,
if any, thus we are not able to assuredly suggest the period or existence
of this prospective non-transiting planet around Kepler-113.
Note (2): Each planet's radius is measured using the combined RV/photometry
analysis, consistent with the best values found for the stellar mass
and radius. Errors are dominated by uncertainties in the stellar
radius.
Note (3): Each planet mass is calculated using the combined RV/photometry
analysis. The stellar parameters are those found in Table 1. The peak
of the posterior distribution for the planet mass is chosen as the
best value. The peak can have either a positive or negative value.
Note (4): We choose the 95th percentile of the MCMC distribution as the upper
limit to the mass. We choose to list this value for all planets, but
these values are more meaningful when the mass detection is marginal
or the mass is poorly constrained.
Note (5): Planets with measurements of density greater than 5g/cm3 are typed
with bold font, including only those with RV mass detections at the
2σ level or better. These planets likely have interior
compositions that are mostly rock and iron/nickel. We caution that
planets having measured densities only 2-3σ above zero require
more RV measurements to secure their rocky nature. Two other planets
with densities between 4-5g/cm3 are also likely rocky, namely
Kepler-102e and Kepler-48c.
Note (6): The RV amplitude listed is the peak of the posterior distribution for
the combined RV/photometry fit. Uncertainties are determining by
integrating the posterior distribution out from the peak value until
68% of the values in the MCMC chain are included.
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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- 10 A10 --- Kepler Source identifier (Kepler number; except for
KOI-1612)
12- 22 F11.6 d BJD Barycentric Julian Date; (BJD-2450000)
24- 30 F7.2 m/s RVel [-285.2/99.3] Radial velocity
32- 36 F5.2 m/s e_RVel [2/25] Uncertainty in RVel
38- 43 F6.3 [-] logR'HK [-6.8/0]? The logR'HK chromospheric
activity value
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 01-Apr-2014