J/ApJ/800/135 HARPS-N radial velocities of KOI-69 (Dressing+, 2015)
The mass of Kepler-93b and the composition of terrestrial planets.
Dressing C.D., Charbonneau D., Dumusque X., Gettel S., Pepe F.,
Collier Cameron A., Latham D.W., Molinari E., Udry S., Affer L.,
Bonomo A.S., Buchhave L.A., Cosentino R., Figueira P., Fiorenzano A.F.M.,
Harutyunyan A., Haywood R.D., Johnson J.A., Lopez-Morales M., Lovis C.,
Malavolta L., Mayor M., Micela G., Motalebi F., Nascimbeni V.,
Phillips D.F., Piotto G., Pollacco D., Queloz D., Rice K., Sasselov D.,
Segransan D., Sozzetti A., Szentgyorgyi A., Watson C.
<Astrophys. J., 800, 135 (2015)>
=2015ApJ...800..135D 2015ApJ...800..135D
ADC_Keywords: Stars, double and multiple ; Radial velocities ; Planets
Keywords: planetary systems; planets and satellites: composition;
stars: individual: Kepler-93 = KOI 69 = KIC 3544595;
techniques: radial velocities
Abstract:
Kepler-93b is a 1.478±0.019R⊕ planet with a 4.7day period
around a bright (V=10.2), astroseismically characterized host star
with a mass of 0.911±0.033M☉ and a radius of
0.919±0.011R☉. Based on 86 radial velocity observations
obtained with the HARPS-N spectrograph on the Telescopio Nazionale
Galileo and 32 archival Keck/HIRES observations, we present a precise
mass estimate of 4.02±0.68M⊕. The corresponding high density
of 6.88±1.18g/cm3 is consistent with a rocky composition of
primarily iron and magnesium silicate. We compare Kepler-93b to other
dense planets with well-constrained parameters and find that between 1
and 6M⊕, all dense planets including the Earth and Venus are
well-described by the same fixed ratio of iron to magnesium silicate.
There are as of yet no examples of such planets with masses
>6M⊕. All known planets in this mass regime have lower
densities requiring significant fractions of volatiles or H/He gas. We
also constrain the mass and period of the outer companion in the
Kepler-93 system from the long-term radial velocity trend and archival
adaptive optics images. As the sample of dense planets with
well-constrained masses and radii continues to grow, we will be able
to test whether the fixed compositional model found for the seven
dense planets considered in this paper extends to the full population
of 1-6M⊕ planets.
Description:
We obtained 86 spectra of Kepler-93 using the HARPS-N spectrograph
(R∼115000) on the 3.57m Telescopio Nazionale Galileo (TNG) at the
Observatorio del Roque de los Muchachos. We acquired 38 and 49 HARPS-N
observations of Kepler-93 during the 2013 and 2014 observing seasons,
respectively (see table 1).
Our full data set included RVs from four seasons of archival HIRES
observations (2009 July-2012 September; see Marcy et al., 2014,
J/ApJS/210/20) and two seasons of HARPS-N observations (2013 June-2014
October).
Objects:
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RA (ICRS) DE Designation(s) (P=Per (d))
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19 25 40.39 +38 40 20.4 Kepler-93 = KOI-69 (P=4.72674)
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 51 86 HARPS-N radial velocity observations of Kepler-93
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See also:
V/133 : Kepler Input Catalog (Kepler Mission Team, 2009)
J/ApJS/211/2 : Revised properties of Q1-16 Kepler targets (Huber+, 2014)
J/ApJS/210/20 : Small Kepler planets radial velocities (Marcy+, 2014)
J/ApJS/210/19 : Kepler planetary candidates. IV. 22 months (Burke+, 2014)
J/A+A/566/A103 : Kepler planet host candidates imaging (Lillo-Box+, 2014)
J/ApJS/208/16 : Kepler transit timing observations. VIII. (Mazeh+, 2013)
J/ApJ/767/127 : Asteroseismic solutions for 77 Kepler stars (Huber+, 2013)
J/A+A/547/A36 : Chemical abundances of 87 KOIs (Adibekyan++, 2012)
J/PASP/124/1279 : Q3 Kepler's combined photometry (Christiansen+, 2012)
J/AJ/144/24 : The Kepler-INT survey (Greiss+, 2012)
J/AJ/142/112 : KIC photometric calibration (Brown+, 2011)
J/ApJ/736/19 : Kepler planetary candidates. II. (Borucki+, 2011)
J/A+A/449/723 : Atmospheres of stars with planets (Gilli+, 2006)
J/A+A/438/251 : Abundances in stars with giant planets (Beirao+, 2005)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 14 F14.6 d BJD Barycentric Julian Date; UTC
16- 23 F8.2 m/s RVel [27331/27356] Radial velocity
25- 28 F4.2 m/s e_RVel [0.7/2.2] Uncertainty in RVel
30- 35 F6.2 m/s BS [-41.2/-22.2] Bisector span
37- 41 F5.2 [-] logR'HK [-5.1/-4.9] The logR'HK chromospheric
activity value
43- 46 F4.2 [-] e_logR'HK [0/0.03] Uncertainty in logR'HK
48- 51 I4 s Exp [900/1800] Exposure Time
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 03-Jul-2015