J/AJ/157/174 Transiting planets in Kepler-47 circumbinary system (Orosz+, 2019)
Discovery of a third transiting planet in the Kepler-47 circumbinary system.
Orosz J.A., Welsh W.F., Haghighipour N., Quarles B., Short D.R., Mills S.M.,
Satyal S., Torres G., Agol E., Fabrycky D.C., Jontof-Hutter D.,
Windmiller G., Muller T.W.A., Hinse T.C., Cochran W.D., Endl M., Ford E.B.,
Mazeh T., Lissauer J.J.
<Astron. J., 157, 174 (2019)>
=2019AJ....157..174O 2019AJ....157..174O (SIMBAD/NED BibCode)
ADC_Keywords: Binaries, eclipsing ; Exoplanets ; Radial velocities ; Ephemerides
Keywords: binaries: eclipsing - planets and satellites: detection -
planets and satellites: fundamental parameters -
stars: fundamental parameters
Abstract:
Of the nine confirmed transiting circumbinary planet systems, only
Kepler-47 is known to contain more than one planet. Kepler-47 b (the
"inner planet") has an orbital period of 49.5 days and a radius of about
3 R⊕. Kepler-47 c (the "outer planet") has an orbital period
of 303.2 days and a radius of about 4.7 R⊕. Here we report the
discovery of a third planet, Kepler-47 d (the "middle planet"), which has
an orbital period of 187.4 days and a radius of about 7 R⊕. The
presence of the middle planet allows us to place much better constraints
on the masses of all three planets, where the 1σ ranges are less
than 26 M⊕, between 7-43 M⊕, and between 2-5 M⊕
for the inner, middle, and outer planets, respectively. The middle and
outer planets have low bulk densities, with ρmiddle<0.68 g/cm3
and ρouter<0.26 g/cm3 at the 1σ level. The two outer planets
are "tightly packed", assuming the nominal masses, meaning no other planet
could stably orbit between them. All of the orbits have low eccentricities
and are nearly coplanar, disfavoring violent scattering scenarios and
suggesting gentle migration in the protoplanetary disk.
Description:
We used 11 radial velocity measurements of the primary in the original
work (Orosz et al. 2012, J/other/Sci/337.1511). Four of these came from
the HRS spectrograph on the Hobby-Eberly Telescope (HET), six of these
came from the Tull Coude spectrograph on the Harlan J. Smith 2.7 m
telescope (HJST) at McDonald Observatory, and one measurement came from
the HIRES spectrograph on the Keck I telescope. Since that time,
Kostov et al. (2013ApJ...770...52K 2013ApJ...770...52K) have provided an additional four
measurements with the SOPHIE spectrograph on the 1.93 m telescope at
Haute-Provence Observatory. We measured the times of the primary and
secondary eclipses using the technique outlined in Welsh et al. (2012,
J/other/Nat/481.475) and Orosz et al. (2012, J/other/Sci/337.1511).
Objects:
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RA (ICRS) DE Designation(s)
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19 41 11.50 +46 55 13.7 Kepler-47 = KIC 10020423
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 71 15 Radial velocities for Kepler-47
table2.dat 76 43 Times and durations of planetary transits
table3.dat 59 197 Times of stellar eclipses
table10.dat 67 87 Times, durations, and impact parameters of
future planet transits
table11.dat 86 176 Planetary mass and radius data
refs.dat 43 57 List of references
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See also:
J/other/Nat/481.475 : Radial velocities of Kepler-34b & Kepler-35b
(Welsh+, 2012)
J/other/Sci/337.1511 : Kepler-47 transits (Orosz+, 2012)
J/ApJ/812/46 : Transit metric for Q1-Q17 Kepler candidates
(Thompson+, 2015)
J/AJ/151/68 : Kepler Mission. VII. Eclipsing binaries in DR3
(Kirk+, 2016)
J/AJ/152/158 : Final Kepler transiting planet search (DR25)
(Twicken+, 2016)
J/ApJS/224/12 : Kepler planetary candidates. VII. 48-month
(Coughlin+, 2016)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 22 A22 --- Obs.Date UT observation date (YYYY-MM-DDThh:mm:ss.ss)
24- 33 F10.5 d BJD [1028.05942/1178.3126] Barycentric Julian Date
(BJD-2455000)
35- 41 F7.3 km/s RV [-26.743/35.458] Uncorrected radial velocity
43- 47 F5.3 km/s e_RV [0.011/0.44] Uncertainty in RV
49- 55 F7.3 km/s RVc [-31.311/30.89]? Corrected radial velocity (1)
57- 61 F5.3 km/s e_RVc [0.054/0.792]? Uncertainty in RVc with scaled
error bar (1)
63- 71 A9 --- Tel Telescope (1)
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Note (1): Given that we have only one measurement from Keck, we cannot determine
the systematic offset and we do not use that measurement in our analysis.
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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- 1 A1 --- Planet [imo] Planet position (G1)
3- 6 F4.1 --- Cycle [1/31] Cycle
8- 17 F10.5 d Time [-30.80969/1408.9602]? Measured time
(BJD-2455000)
19- 23 F5.2 min e_Time [3.35/70.76]? Uncertainty in Time
25- 29 F5.2 h Dur [1.12/10.83]? Measured duration
31- 34 F4.2 h e_Dur [0.19/3.83]? Uncertainty in Dur
36- 45 F10.5 d Time-m [-30.80876/1408.96429] Model time (BJD-2455000)
47- 51 F5.2 h Dur-m [0.9/10.45] Model duration
53- 56 F4.2 --- b [0.28/0.99] Impact parameter
58- 76 A19 --- Note Cause of missing measured values
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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- 5 F5.1 --- Cycle [0/196] Cycle
7- 16 F10.5 d Tp [-29.30551/1423.12757]? Primary time
(BJD-2455000)
18- 27 F10.5 d Tp-c [-29.30557/1423.12767]? Corrected time
(BJD-2455000)
29- 32 F4.2 min e_Tp [0.47/0.92]? Time uncertainty
34- 43 F10.6 --- Cycle2 [0.487385/194.487381]? Cycle, fractional
45- 54 F10.5 d Ts [-33.12242/1411.86157]? Secondary time
(BJD-2455000)
56- 59 F4.2 min e_Ts [2.21/3.7]? Uncertainty in Ts
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Byte-by-byte Description of file: table10.dat
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Bytes Format Units Label Explanations
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1- 1 A1 --- Planet [imo] Planet position (G1)
3- 12 F10.5 d BJD [3522.04361/6402.38804] Transit Barycentric
Julian Date (BJD-2455000)
14- 20 F7.5 d e_BJD [0.01449/0.27883] Uncertainty in BJD
22- 43 A22 --- Obs.Date UT transit date (YYYY-MMM-DDThh:mm:ss.s)
45- 49 F5.3 --- b [0.006/0.637] Impact parameter
51- 55 F5.3 --- e_b [0.007/0.065] Uncertainty in b
57- 61 F5.2 h Dur [3.07/34.28] Duration
63- 67 F5.2 h e_Dur [0.01/21.7] Uncertainty in Dur
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Byte-by-byte Description of file: table11.dat
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Bytes Format Units Label Explanations
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1- 13 A13 --- Planet Planet name
15- 19 F5.2 Mgeo Mass [0.03/26.7] Planet mass
21- 26 F6.3 Mgeo E_Mass [0.04/23.84] Upper uncertainty in Mass
28- 33 F6.3 Mgeo e_Mass [0.02/11.67] Lower uncertainty in Mass
35- 39 F5.3 Rgeo Rp [0.52/9.7] Planet radius
41- 45 F5.3 Rgeo E_Rp [0.02/2.8] Upper uncertainty in Rp
47- 51 F5.3 Rgeo e_Rp [0.02/1.8] Lower uncertainty in Rp
53- 60 F8.3 Earth Sp [0.383/4763.9] Planet insolation flux
62- 68 F7.3 Earth E_Sp [0.036/535.4] Upper uncertainty in Sp
70- 76 F7.3 Earth e_Sp [0.036/535.4] Lower uncertainty in Sp
78- 86 A9 --- Ref Reference(s) (see refs.dat file)
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Byte-by-byte Description of file: refs.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- Ref [1/57] Reference code
4- 23 A20 --- Aut Author's name(s)
25- 43 A19 --- Bibcode Bibcode of the reference
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Global notes:
Note (G1): Planet position as follows:
i = Inner planet;
m = Middle planet;
o = Outer planet.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Tiphaine Pouvreau [CDS] 22-Jul-2019