J/AJ/155/161 Stars nearby Robo-AO Kepler planetary candidates (Ziegler+, 2018)
Robo-AO Kepler survey.
IV. The effect of nearby stars on 3857 planetary candidate systems.
Ziegler C., Law N.M., Baranec C., Riddle R., Duev D.A., Howard W.,
Jensen-Clem R., Kulkarni S.R., Morton T., Salama M.
<Astron. J., 155, 161 (2018)>
=2018AJ....155..161Z 2018AJ....155..161Z (SIMBAD/NED BibCode)
ADC_Keywords: Exoplanets ; Stars, double and multiple ; Photometry ; Optical ;
Stars, diameters
Keywords: binaries: close - instrumentation: adaptive optics -
methods: data analysis - methods: observational -
planets and satellites: detection -
techniques: high angular resolution
Abstract:
We present the overall statistical results from the Robo-AO Kepler
planetary candidate survey, comprising of 3857 high-angular resolution
observations of planetary candidate systems with Robo-AO, an automated
laser adaptive optics system. These observations reveal previously
unknown nearby stars blended with the planetary candidate host stars
that alter the derived planetary radii or may be the source of an
astrophysical false positive transit signal. In the first three papers
in the survey, we detected 440 nearby stars around 3313 planetary
candidate host stars. In this paper, we present observations of
532 planetary candidate host stars, detecting 94 companions around
88 stars; 84 of these companions have not previously been observed in
high resolution. We also report 50 more-widely separated companions
near 715 targets previously observed by Robo-AO. We derive corrected
planetary radius estimates for the 814 planetary candidates in systems
with a detected nearby star. If planetary candidates are equally
likely to orbit the primary or secondary star, the radius estimates
for planetary candidates in systems with likely bound nearby stars
increase by a factor of 1.54, on average. We find that 35 previously
believed rocky planet candidates are likely not rocky due to the
presence of nearby stars. From the combined data sets from the
complete Robo-AO KOI survey, we find that 14.5±0.5% of planetary
candidate hosts have a nearby star with 4", while 1.2% have two
nearby stars, and 0.08% have three. We find that 16% of Earth-sized,
13% of Neptune-sized, 14% of Saturn-sized, and 19% of Jupiter-sized
planet candidates have detected nearby stars.
Description:
The objective of the Robo-AO Kepler survey is to perform high-resolution
observations of every KOI. We therefore targeted KOIs not observed in
Law et al. 2014, J/ApJ/791/35 (Paper I), Baranec et al. 2016, J/AJ/152/18
(Paper II), or Ziegler et al. 2017, J/AJ/153/66 (Paper III) from the Kepler
DR25 catalog based on Q1-Q17 data (Borucki et al. 2010ApJ...713L.126B 2010ApJ...713L.126B,
2011, J/ApJ/728/117, J/ApJ/736/19; Batalha et al. 2013, J/ApJS/204/24;
Burke et al. 2014, J/ApJS/210/19; Rowe et al. 2014, J/ApJ/784/45;
Coughlin et al. 2016, J/ApJS/224/12; Mathur et al. 2017, J/ApJS/229/30).
Observations of these targets presented in this paper are from the 2016
observing season.
We obtained high-angular-resolution images of 532 KOIs not previously
observed by Robo-AO during 18 separate nights of observations between
2016 June 08 and 2016 July 15 (UT), detailed in Table 9 in the Appendix.
The observations were performed using the Robo-AO laser adaptive optics
system (Riddle et al. 2012SPIE.8447E..2OR; Baranec et al.
2013JVE....7250021B, 2014ApJ...790L...8B 2014ApJ...790L...8B) mounted on the Kitt Peak 2.1 m
telescope (Jensen-Clem et al. 2018AJ....155...32J 2018AJ....155...32J), masked to a 1.85 m
aperture. The AO system runs at a loop rate of 1.2 kHz to correct
high-order wavefront aberrations. Observations were taken in a long-pass
filter cutting on at 600 nm (LP600 hereafter). The LP600 filter
approximates the Kepler passband at redder wavelengths, while also
suppressing blue wavelengths that reduce adaptive optics performance.
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 75 94 Detections of objects nearby 532 previously
unpublished Kepler planet candidates
table3.dat 75 51 Detections of objects outside 2.5" and within
4.0" of Kepler planet candidates from
Law et al. (2014, J/ApJ/791/35) targets
table8.dat 53 809 Implications on derived radius of Kepler
planetary candidates
table9.dat 37 532 Full Robo-AO observation list
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See also:
V/133 : Kepler Input Catalog (Kepler Mission Team, 2009)
J/ApJ/728/117 : Kepler planetary candidates. I. (Borucki+, 2011)
J/ApJ/736/19 : Kepler planetary candidates. II. (Borucki+, 2011)
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/ApJS/204/24 : Kepler planetary candidates. III. (Batalha+, 2013)
J/ApJ/784/45 : Kepler's multiple planet candidates. III. (Rowe+, 2014)
J/ApJ/791/35 : Detection of 715 Kepler planet candidates host stars
(Law+, 2014)
J/ApJS/210/19 : Kepler planetary candidates. IV. 22 months (Burke+, 2014)
J/ApJ/806/248 : AO imaging of KOIs with gas giant planets (Wang+, 2015)
J/ApJ/813/130 : Kepler multiple transiting planet systems (Wang+, 2015)
J/AJ/152/8 : Impact of stellar multiplicity on planetary systems I.
(Kraus+, 2016)
J/AJ/152/18 : Robo-AO Kepler planetary candidate survey. II. (Baranec+, 2016)
J/ApJS/224/12 : Kepler planetary candidates. VII. 48-month (Coughlin+, 2016)
J/AJ/153/25 : Near-infrared observations of 84 KOI systems (Atkinson+, 2017)
J/AJ/153/66 : Robo-AO Kepler Planetary Candidate Survey. III.
(Ziegler+, 2017)
J/AJ/153/71 : Kepler follow-up observation program. I. Imaging
(Furlan+, 2017)
J/AJ/153/117 : KOIs companions from high-resolution imaging (Hirsch+, 2017)
J/ApJS/229/30 : Revised stellar properties of Q1-17 Kepler targets
(Mathur+, 2017)
http://exoplanetarchive.ipac.caltech.edu/ : NASA exoplanet archive
Byte-by-byte Description of file: table1.dat table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 A4 --- KOI Kepler Object of Interest identifier (KOI-NNNN
in Simbad)
6- 11 F6.3 mag Kpmag [7.899/18.59] Kepler apparent magnitude
13- 23 A11 "date" Date Date of the observation
25- 29 A5 --- Filt Filter (LP600 or i)
31- 34 F4.1 --- sigma [3/60.1] Detection significance of detected
companions σ
36- 39 F4.2 arcsec Sep [0.53/3.95] Separation
41- 44 F4.2 arcsec e_Sep [0.06] Uncertainty in Sep
46- 48 I3 deg PA [0/357] Position angle
50 I1 deg e_PA [2/6]? Uncertainty in PA
52- 56 F5.2 mag Dmag [-0.67/6.92] Magnitude difference
58- 61 F4.2 mag e_Dmag [0/1.58] Uncertainty in Dmag
63- 75 A13 --- Ref Reference of previous high-resolution observation
(1)
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Note (1): References for previous high-resolution observations are denoted using
the following codes:
L12 = Lillo-Box et al. (2012, J/A+A/546/A10);
F17 = Furlan et al. (2017, J/AJ/153/71);
A12 = Adams et al. (2012, J/AJ/144/42);
D14 = Dressing et al. (2014AJ....148...78D 2014AJ....148...78D);
K16 = Kraus et al. (2016, J/AJ/152/8);
W15 = Wang et al. (2015, J/ApJ/806/248);
B16 = Baranec et al. (2016, J/AJ/152/18).
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Byte-by-byte Description of file: table8.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 7 A7 --- KOI Planet candidate KOI number (KOI-NNNN.NN in Simbad)
9- 12 F4.2 arcsec Sep [0.21/4.54] Separation
14- 18 F5.2 mag Dmag [-0.36/7.22] Magnitude difference between target
and secondary Δm
20- 21 A2 --- Ref Reference code for nearby star detection (1)
23- 27 F5.2 Rsun R*(p) [0.12/13.55] Primary stellar radius (2)
29- 32 F4.2 Rsun R*(s) [0.22/2.58] Estimated secondary stellar radius (3)
34- 39 F6.2 Rgeo Rp [0.35/576.1] Original planetary radius estimate (4)
41- 46 F6.2 Rgeo Rp(p) [0.35/589.4] Estimated eclipsing object radius (5)
48- 53 F6.1 Rgeo Rp(s) [0.7/1392] Estimated eclipsing object radius (6)
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Note (1): Reference code as follows:
P1 = Law et al. (2014, J/ApJ/791/35);
P2 = Baranec et al. (2016, J/AJ/152/18);
P3 = Ziegler et al. (2017, J/AJ/153/66);
TW = This work.
Note (2): From Mathur et al. (2017, J/ApJS/229/30).
Note (3): In the scenario where it is bound to the primary star, using absolute
magnitude difference in the Kepler band and the Dartmouth stellar models
(Dotter et al. 2008ApJS..178...89D 2008ApJS..178...89D).
Note (4): From NASA Exoplanet Archive
Note (5): In the scenario where it is physically bound to the target star,
corrected for transit dilution caused by the presence of either bound or
unbound nearby stars.
Note (6): Estimated eclipsing object radius in the scenario where it is bound
to the companion star, correcting for transit dilution by nearby stars and
using the stellar radius estimate of the companion in this table.
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Byte-by-byte Description of file: table9.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 A6 --- KOI Kepler Object of Interest identifier (K0NNNN)
8- 12 F5.2 mag Kpmag [7.9/18.79] Kepler apparent magnitude
14- 24 A11 "date" Date Date of the observation
26- 31 A6 --- Qual Observation quality (high, medium or low) (1)
33- 35 A3 --- Comp [yes ] Companion detected?
37 I1 --- Np [0/8] Number of planetary candidate(s) in Table 8
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Note (1): The two dominant factors that affect the image performance of the
Robo-AO system are seeing and target brightness. An automated routine was used
to classify the image performance for each target. The code uses PSF core size
as a proxy for image performance. Observations were binned into three
performance groups, with 31% fall in the low-performance group, 41% in the
medium performance group, and 28% in the high-performance group.
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History:
From electronic version of the journal
References:
Law et al. Paper I. 2014ApJ...791...35L 2014ApJ...791...35L, Cat. J/ApJ/791/35
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 V. 2018AJ....156...83Z 2018AJ....156...83Z
(End) Prepared by [AAS], Tiphaine Pouvreau [CDS] 15-Nov-2018