J/ApJ/791/35 Detection of 715 Kepler planet candidates host stars (Law+, 2014)
Robotic laser adaptive optics imaging of 715 Kepler exoplanet candidates
using Robo-AO.
Law N.M., Morton T., Baranec C., Riddle R., Ravichandran G., Ziegler C.,
Johnson J.A., Tendulkar S.P., Bui K., Burse M.P., Das H.K., Dekany R.G.,
Kulkarni S., Punnadi S., Ramaprakash A.N.
<Astrophys. J., 791, 35 (2014)>
=2014ApJ...791...35L 2014ApJ...791...35L (SIMBAD/NED BibCode)
ADC_Keywords: Stars, double and multiple ; Planets ; Magnitudes ;
Binaries, eclipsing
Keywords: binaries: close - instrumentation: adaptive optics -
instrumentation: high angular resolution - methods: data analysis -
methods: observational - planetary systems -
planets and satellites: detection -
planets and satellites: fundamental parameters
Abstract:
The Robo-AO Kepler Planetary Candidate Survey is observing every
Kepler planet candidate host star with laser adaptive optics imaging
to search for blended nearby stars, which may be physically associated
companions and/or responsible for transit false positives. In this
paper, we present the results from the 2012 observing season,
searching for stars close to 715 Kepler planet candidate hosts. We
find 53 companions, 43 of which are new discoveries. We detail the
Robo-AO survey data reduction methods including a method of using the
large ensemble of target observations as mutual point-spread-function
references, along with a new automated companion-detection algorithm
designed for large adaptive optics surveys. Our survey is sensitive to
objects from ∼ 0.15'' to 2.5'' separation, with magnitude
differences up to Δm ∼ 6. We measure an overall
nearby-star probability for Kepler planet candidates of 7.4%±1.0%,
and calculate the effects of each detected nearby star on the
Kepler-measured planetary radius. We discuss several Kepler Objects of
Interest (KOIs) of particular interest, including KOI-191 and
KOI-1151, which are both multi-planet systems with detected stellar
companions whose unusual planetary system architecture might be best
explained if they are "coincident multiple" systems, with several
transiting planets shared between the two stars. Finally, we find 98%
confidence evidence that short-period giant planets are two to three
times more likely than longer-period planets to be found in wide
stellar binaries.
Description:
We selected targets from the KOIs catalog based on a Q1-Q6 Kepler
data search (Batalha et al. 2013, J/ApJS/204/24). Our initial targets
were selected randomly from the Q1-Q6 KOIs, requiring only that the
targets are brighter than mi = 16.0, a restriction which removed
only 2% of the KOIs. While it is our intent to observe every KOI with
Robo-AO, this initial target selection provides a wide coverage of the
range of KOI properties. Given Robo-AO's low time overheads, we took
the time to re-observe KOIs which already had detected companions, to
produce a complete and homogenous survey. We obtained
high-angular-resolution images of the 715 Kepler targeted planet
candidate host stars in summer 2012. We performed all the observations
in a queue-scheduled mode with the Robo-AO laser adaptive optics
system (Baranec et al. 2012SPIE.8447E..04B 2012SPIE.8447E..04B; 2013, J. Visualized Exp.,
72, e50021; Riddle et al. 2012SPIE.8447E..2OR) mounted on the robotic
Palomar 60 inch telescope (Cenko et al. 2006PASP..118.1396C 2006PASP..118.1396C).
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table2.dat 82 38 Secure Detections of Objects within 2.5'' of
Kepler Planet Candidates
table3.dat 65 15 Likely Detections of Objects within 2.5'' of
Kepler Planet Candidates
table4.dat 56 75 Implications on Derived Radius of Kepler
Planet Candidates
table5.dat 45 715 Full Robo-AO Observation List
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See also:
V/133 : Kepler Input Catalog (Kepler Mission Team, 2009)
J/AJ/142/19 : Speckle observations of KOI (Howell+, 2011)
J/A+A/546/A10 : Multiplicity in transiting planet-host stars
(Lillo-Box+, 2012)
J/AJ/143/137 : Minima of 41 eclipsing binaries from a Kepler survey
(Gies+, 2012)
J/AJ/144/42 : Infrared photometry of 90 KOIs (Adams+, 2012)
J/ApJS/204/24 : Kepler planetary candidates. III. (Batalha+, 2013)
J/MNRAS/436/1883 : Properties of KOI host stars (Walkowicz+, 2013)
J/ApJ/832/183 : Binary stellar evolution data for Kepler systems
(Kostov+, 2016)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 A8 --- KOI Kepler Object of Interest identifier
(KOI-NNNN)
10- 13 F4.1 mag imag ? i-band apparent magnitude
15- 25 A11 "date" Date KOI observation date
27- 31 A5 --- Filter [i/LP600 ] Filter used for the
observation
33- 35 I3 --- Signi ?=- Detection significance in sigma unit
37- 40 F4.2 arcsec Sep Detectable separation range
42- 45 F4.2 arcsec e_Sep Error on Sep
47- 49 I3 deg PA ?=- Position angle
51 I1 deg e_PA ? Error on PA
53- 56 F4.2 mag magdiff Magnitude difference in the Kepler band
58- 61 F4.2 mag e_magdiff ? Error on magdiff
62- 63 A2 --- Ks Ks if magnitude difference in Ks-band
65- 82 A18 --- PrevDetec Previous detection (1)
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Note (1): References as follows:
A12 = Adams et al. 2012, J/AJ/144/42;
A13 = Adams et al. 2013AJ....146....9A 2013AJ....146....9A;
B11 = Buchhave et al. 2011ApJS..197....3B 2011ApJS..197....3B;
D09 = Daemgen et al. 2009A&A...498..567D 2009A&A...498..567D;
H12 = Horch et al. 2012AJ....144..165H 2012AJ....144..165H;
H11 = Howell et al. 2011, J/AJ/142/19;
L12 = Lillo-Box et al. 2012, J/A+A/546/A10.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 A8 --- KOI Kepler Object of Interest identifier
(KOI-NNNN)
10- 13 F4.1 mag imag i-band apparent magnitude
15- 25 A11 "date" Date KOI observation date
27- 31 A5 --- Filter [i/LP600 ] Filter used for the observation
33- 35 F3.1 --- Signi Detection significance in sigma unit
37- 40 F4.2 arcsec Sep Detectable separation range
42- 45 F4.2 arcsec e_Sep Error on Sep
47- 49 I3 deg PA Position angle
51 I1 deg e_PA Error on PA
53- 56 F4.2 mag magdiff Magnitude difference in the Kepler band
58- 61 F4.2 mag e_magdiff Error on magdiff
63- 65 A3 --- PrevDetec Previous detection (1)
--------------------------------------------------------------------------------
Note (1): References as follows :
A12 = Adams et al. 2012, J/AJ/144/42;
L12 = Lillo-Box et al. 2012, J/A+A/546/A10.
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Byte-by-byte Description of file: table4.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 7 F7.2 --- KOI Kepler Object of Interest identifier (NNNN.NN)
9- 15 F7.3 d P Period (1)
17- 21 F5.2 Rgeo Rp Planet radius (1)
23- 26 F4.2 Rsun RA ?=- Estimated radius of the target star (1)
28- 30 F3.1 mag magdiff ?=- Magnitude difference in the Kepler band
32- 35 F4.2 arcsec Sep ?=- Detectable separation range
37- 40 F4.2 Rsun RB ?=- Estimated radius of the stellar
companion (2)
42- 45 F4.1 Rgeo RpA Eclipsing target star radius (3)
47- 50 F4.1 Rgeo RpB Eclipsing stellar companion radius
52- 56 F5.1 Rgeo RpBbg Eclipsing stellar companion radius (4)
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Note (1): Values taken from the NASA Exoplanet Archive.
Note (2): In the scenario where it is physically bound to the target star.
Estimate made according to the absolute magnitude difference in the Kepler
band, according the Dartmouth stellar models
(Dotter et al. 2008ApJS..178...89D 2008ApJS..178...89D).
Note (3): In the scenario where the companion star is the eclipsed object and
is physically bound to the target star, assuming the stellar radius of star
B as estimated in this table.
Note (4): In the scenario where the companion star is the eclipsed object and
is a chance-aligned background star with radius 1 R☉. We note that a
background or foreground object is perhaps unlikely to be solar-type, but
this quantification allows for simple scaling of the implied eclipsing object
radius.
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Byte-by-byte Description of file: table5.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 A9 --- KOI Kepler Object of Interest identifier (K0NNNN.NN)
11- 16 F6.3 mag imag ? i-band apparent magnitude
18- 28 A11 "date" Date KOI observation date
30- 34 A5 --- Filter [i/LP600 ] Filter used for the observation
36- 41 A6 --- Obsqual [high/medium/low ] Observation quality
43- 45 A3 --- Comp [yes ] Presence of detected companion
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History:
From electronic version of the journal
References:
Baranec et al. Paper II. 2016AJ....152...18B 2016AJ....152...18B, Cat. J/AJ/152/18
Ziegler et al. Paper III. 2017AJ....153...66Z 2017AJ....153...66Z, Cat. J/AJ/153/66
Ziegler et al. Paper IV. 2018AJ....155..161Z 2018AJ....155..161Z, Cat. J/AJ/155/161
Ziegler et al. Paper V. 2018AJ....156...83Z 2018AJ....156...83Z
(End) Prepared by Tiphaine Pouvreau [CDS] 24-Mar-2017