J/AJ/152/18 Robo-AO Kepler planetary candidate survey. II. (Baranec+, 2016)
Robo-AO Kepler planetary candidate survey. II. Adaptive optics imaging of 969
Kepler exoplanet candidate host stars.
Baranec C., Ziegler C., Law N.M., Morton T., Riddle R., Atkinson D.,
Schonhut J., Crepp J.
<Astron. J., 152, 18-18 (2016)>
=2016AJ....152...18B 2016AJ....152...18B (SIMBAD/NED BibCode)
ADC_Keywords: Stars, double and multiple ; Planets ; Photometry, infrared
Keywords: binaries: close - instrumentation: adaptive optics -
instrumentation: high angular resolution - planetary systems -
planets and satellites: detection -
planets and satellites: fundamental parameters
Abstract:
We initiated the Robo-AO Kepler Planetary Candidate Survey in 2012 to
observe each Kepler exoplanet candidate host star with high angular
resolution, visible light, laser adaptive optics (AOs) imaging. Our
goal is to find nearby stars lying in Kepler's photometric apertures
that are responsible for the relatively high probability of
false-positive exoplanet detections and that cause underestimates of
the size of transit radii. Our comprehensive survey will also shed
light on the effects of stellar multiplicity on exoplanet properties
and will identify rare exoplanetary architectures. In this second part
of our ongoing survey, we observed an additional 969 Kepler planet
candidate hosts and we report blended stellar companions up to
Δm~6 that contribute to Kepler's measured light curves.
We found 203 companions within ∼4'' of 181 of the Kepler stars, of
which 141 are new discoveries. We measure the nearby star probability
for this sample of Kepler planet candidate host stars to be
10.6%±1.1% at angular separations up to 2.5'', significantly higher
than the 7.4%±1.0% probability discovered in our initial sample of
715 stars; we find the probability increases to 17.6%±1.5% out to a
separation of 4.0''. The median position of Kepler Objects of Interest
(KOIs) observed in this survey are 1.1° closer to the galactic
plane, which may account for some of the nearby star probability
enhancement. We additionally detail 50 Keck AO images of Robo-AO
observed KOIs in order to confirm 37 companions detected at a
<5σ significance level and to obtain additional infrared
photometry on higher significance detected companions.
Description:
We selected targets that we had not previously observed from the KOI
Catalog based on the Q1-Q12 Kepler data (Rowe et al. 2015, Cat.
J/ApJS/217/16). These targets were added to the Robo-AO intelligent
observing queue and observed during the summer of 2013.
We obtained high angular resolution images of 956 Kepler planet
candidate host stars with the Robo-AO robotic laser AOs system over
the course of 19 nights between 2013 July 21 and 2013 October 25,
detailed in Table5. We also include 13 images from 2012 (2012 July
16-September 13) that required additional confirmation of the KOI
position in the Robo-AO field of view. All the observations were
performed in a queue-scheduled mode in combination with other science
programs using the Robo-AO autonomous laser AO system mounted on the
robotic 1.5m telescope at Palomar Observatory (exposure time: 90s;
observation wavelengths: 600-950nm; FWHM resolution: 0.12''-0.15'';
field of view: 44''*44''; pixel scale: 43.1mas/pix; detector format:
10242 pixels; targets observed/hour: 20).
We obtained images of 50 KOIs with the NIRC2 instrument behind the
Keck II AO system that were previously observed with Robo-AO and had
evidence of a companion. Observations were conducted on 2013 June 25,
2013 August 24 and 25, 2014 August 17, and 2015 July 25 in the K, Ks,
or Kp filters, and in the narrow mode of NIRC2 (9.952mas/pixel).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 86 98 Detections of objects within ∼4.0'' of Kepler
planet candidates at ≥5σ significance
table3.dat 86 105 Detections of objects within ∼4.0'' of Kepler
planet candidates at <5σ significance
table4.dat 62 63 Full Keck-NIRC2 observation list and detected
companions
table5.dat 46 969 Full Robo-AO observation list
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See also:
V/133 : Kepler Input Catalog (Kepler Mission Team, 2009)
J/ApJS/224/12 : Kepler planetary candidates. VII. 48-month (Coughlin+, 2016)
J/ApJ/799/4 : Robo-AO observations of binary stars (Riddle+, 2015)
J/ApJS/217/16 : Kepler planetary candidates. V. 3yr Q1-Q12 (Rowe+, 2015)
J/ApJS/213/5 : Cool KOIs. VI. H- and K- band spectra (Muirhead+, 2014)
J/A+A/566/A103 : Kepler planet host candidates imaging (Lillo-Box+, 2014)
J/A+A/546/A10 : Transiting planet-host stars multiplicity (Lillo-Box+, 2012)
J/AJ/144/42 : Infrared photometry of 90 KOIs (Adams+, 2012)
J/AJ/142/19 : Speckle observations of KOI (Howell+, 2011)
Byte-by-byte Description of file: table[23].dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- --- [KOI-]
5- 8 I4 --- KOI [4/4871] Kepler Object of Interest identifier
10- 13 F4.1 mag imag [9.2/15.8]? The i band magnitude
15- 25 A11 "Y:M:D" Date Date of observation
27- 31 A5 --- Flt Filter (mostly LP600, or i') (1)
33- 37 F5.1 --- Signi [2/613] Significance σ
39- 42 F4.2 arcsec Sep [0.23/4.54] Separation
44- 47 F4.2 arcsec e_Sep [0.06/0.06] Error in Separation
49- 51 I3 deg PA Position angle
53 I1 deg e_PA [2/7] Error in PA
55- 58 F4.2 mag dmag [0.01/6.7] Magnitude difference
60- 63 F4.2 mag e_dmag [0.03/0.51] Error in dmag
65- 80 A16 --- Prev Reference for previous detection(s) (2)
82 A1 --- f_Prev [a] Flag "a" on Prev means that companion
identity is ambiguous (see Section 5.2)
84- 86 A3 --- NIRC2 [yes] NIRC2 detection? (yes)
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Note (1): For the majority of these observations, a long-pass filter with a cut
on wavelength of 600nm was used (LP600). An i'-band filter (York et al.
2000AJ....120.1579Y 2000AJ....120.1579Y) was used during eight of the 2012 observations in an
attempt to obtain slightly sharper images of brighter targets. A comparison
of the two filters can be found in Pap.I (Law et al. 2014ApJ...791...35L 2014ApJ...791...35L).
Note (2): References for previous detections are denoted with following codes:
A12 = Adams et al. 2012 (Cat. J/AJ/144/42);
C15 = Campante et al. 2015ApJ...799..170C 2015ApJ...799..170C;
D14 = Dressing et al. 2014AJ....148...78D 2014AJ....148...78D;
E15 = Everett et al. 2015AJ....149...55E 2015AJ....149...55E;
G16 = Gaidos et al. 2016MNRAS.457.2877G 2016MNRAS.457.2877G;
H11 = Howell et al. 2011 (Cat. J/AJ/142/19);
H12 = Horch et al. 2012 2012AJ....144..165H 2012AJ....144..165H;
K15 = Kolbl et al. 2015AJ....149...18K 2015AJ....149...18K;
K16 = Kraus et al. 2016 (Cat. J/AJ/152/8);
LB12 = Lillo-Box et al. 2012 (Cat. J/A+A/546/A10);
LB14 = Lillo-Box et al. 2014 (Cat. J/A+A/566/A103);
M14 = Muirhead et al. 2014 (Cat. J/ApJS/213/5);
Te15 = Teske et al. 2015 (Cat. 2015AJ....150..144T 2015AJ....150..144T);
To15 = Torres et al. 2015ApJ...800...99T 2015ApJ...800...99T;
W15 = Wang et al. 2015ApJ...813..130W 2015ApJ...813..130W.
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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- 4 A4 --- --- [KOI-]
5- 8 I4 --- KOI [190/4871] Kepler Object of Interest identifier
10- 20 A11 "Y:M:D" Date Date of observation
22- 23 A2 --- Flt Filter (K, Kp, or Ks)
25- 29 F5.3 arcsec Sep [0.18/4.2] Separation
31- 35 F5.3 arcsec e_Sep [0.005/0.01] Error in Sep
37- 39 I3 deg PA [4/357] Position angle
41 I1 deg e_PA [1/3] Error in PA
43- 47 F5.2 mag dmag [-0.26/5.93] Magnitude difference between
companion and primary
49- 52 F4.2 mag e_dmag [0.05/0.34] Error in dmag (1)
54- 58 A5 --- --- [Table]
60 I1 --- Table [2/3]? Number of the table in which the object
detection is presented (2 or 3) (2)
62 A1 --- Note [abc] Additional note (3)
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Note (1): The uncertainty in the magnitude difference is estimated by varying
the aperture radius from 0.5 to 5 of the width of the stellar PSF and
measuring the standard deviation of the difference.
Note (2): The reliability of detection is defined as below:
Table 2 = ≥5σ significance;
Table 3 = <5σ significance.
Note (3): Flag defined as follows:
a = Additional detection not reported in Paper I (Law et al.
2014ApJ...791...35L 2014ApJ...791...35L); angular separation exceeds 2.5'';
b = Companion not detected in the Robo-AO image;
c = Confirmation of <5σ significance companions in Paper I
(Law et al. 2014ApJ...791...35L 2014ApJ...791...35L).
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 2 A2 --- --- [K0]
3- 9 F7.2 --- KOI Kepler Object of Interest identifier
11- 14 F4.1 mag imag [9.2/17]? The i band magnitude
16- 25 A10 "Y:M:D" Date Date of the observation
27- 32 A6 --- Qual Observation quality (low, medium, or high) (1)
34- 40 A7 --- n_Qual Note on Qual (i'-band)
42- 44 A3 --- Comp [yes] Flag for companion (yes)
46 A1 --- f_Comp [d] Flag on Comp (d=companion originally
discovered in image from NIRC2 instrument,
see Table 4)
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Note (1): All observations taken in the LP600 filter unless noted by (i'-band).
See Section 3.5 for full details plus the contrast curves of Fig.2.
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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
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 [AAS]; Sylvain Guehenneux [CDS] 17-Oct-2016