J/A+A/546/A10 Multiplicity in transiting planet-host stars (Lillo-Box+, 2012)
Multiplicity in transiting planet-host stars. A lucky imaging study of Kepler
candidates.
Lillo-Box J., Barrado D., Bouy H.
<Astron. Astrophys., 546, A10-10 (2012)>
=2012A&A...546A..10L 2012A&A...546A..10L
ADC_Keywords: Stars, double and multiple ; Planets ; Photometry, SDSS
Keywords: binaries: visual - instrumentation: high angular resolution -
planets and satellites: fundamental parameters
Abstract:
In the exoplanetary era, the Kepler spacecraft is causing a revolution
by discovering thousands of new planet candidates. However, a
follow-up program is needed to reject false candidates and fully
characterize the bona-fide exoplanets.
Our main aims are to 1./ detect and analyze close companions inside
the typical Kepler point spread function (PSF) to study whether they
are the responsible for the dimming found in Kepler light curves, 2./
study the change in the stellar and planetary parameters caused by an
unresolved object, 3./ help validate the Kepler objects of interest
(KOI) that do not have any object inside the Kepler PSF, and 4./ study
the multiplicity rate of planet-host candidates. Such a large sample
of observed planet-host candidates allows us to derive statistics for
close (visual or bounded) companions to the harboring star.
Description:
We present lucky imaging observations for a total of 98 KOIs. This
technique is based on the acquisition of thousands of
very-short-exposure-time images. A selection and combination of a
small amount of the highest quality frames provides a high resolution
image with objects having a 0.1 arcsec PSF. We apply this technique to
carry out observations in the Sloan i and z filters of our Kepler
candidates.
The data presented in this paper were taken at the Calar Alto
Observatory (Almeria, Spain) during 19 nights of observations divided
into three separate runs (6-12 June 2011, 1-10 July 2011, and
25-26 July 2011).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 18 11 Estimated spectral types for objects with i-z>0.21
table4.dat 59 59 Observing information of the 41 non-isolated
objects in our sample
table5.dat 83 36 Photometric and astrometric results for companions
closer than 3 arcsec detected in our KOI sample
(19 companions to 17 KOIs)
table6.dat 77 57 Photometric and astrometric results for companions
between 3-6 arcsec detected in our KOI sample
(30 companions to 27 KOIs)
table7.dat 74 29 Spectral-energy-distribution fitting results for the
medium-distance companions with 2MASS counterparts
table8.dat 69 23 *New planet-transit depth and relative radii to the
parent star accounting for the blended objects in
the Kepler images
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Note on table8.dat: In this calculation, we have taken into account only the
closest objects (<3arcsec) to the KOI. KOI-0704.01 is not present owing to
the large errors in its δ value.
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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)
Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- --- [KOI-]
5- 8 I4 --- KOI KOI designation
9 A1 --- m_KOI [ABC] Component
11- 12 A2 --- b_SpT Lower Limit spectral type (1)
14- 15 A2 --- SpT Spectral type
17- 18 A2 --- B_SpT Upper Limit spectral type (1)
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Note (1): Second and third columns represent the lower and upper limits
(respectively) for the spectral type determination according to the method
described in the text. Since no decimals have been considered, we estimate
an error of one subclass for those with no differences between the error
limits and the central value.
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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 I4 --- KOI [99/1574] KOI number
6- 7 I2 h RAh Right ascension (J2000) (1)
9- 10 I2 min RAm Right ascension (J2000) (1)
12- 16 F5.2 s RAs Right ascension (J2000) (1)
18 A1 --- DE- Declination sign (J2000) (1)
19- 20 I2 deg DEd Declination (J2000) (1)
22- 23 I2 arcmin DEm Declination (J2000) (1)
25- 28 F4.1 arcsec DEs Declination (J2000) (1)
30- 39 A10 "DD/MM/YYYY" Date Observation date
41- 45 F5.1 s tExp Exposure time (2)
47 A1 --- Filt [iz] Filter
49- 53 F5.2 mag icomp ? Estimated completeness i magnitude (3)
55- 59 F5.2 mag idet ? Estimated detectability i magnitude (3)
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Note (1): Right ascension and Declination from Borucki et al.
(2011, Cat. J/ApJ/736/19).
Note (2): Effective exposure time of the image. As the selection rate was
of 10% for all the images, one must multiply this column by 10 to
obtain the real exposure time.
Note (3): Estimated completeness and detectability magnitudes scaled to the
ones found for the globular cluster M15 (see Sect. 2.3.6) by the
exposure time of each particular image.
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Byte-by-byte Description of file: table[56].dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- KOI [99/1574] KOI number
6 A1 --- m_KOI [ABC] Component
7 A1 --- n_KOI [+*] Note about this component (1)
9- 13 F5.3 arcsec Sep [0/6] Angular separation from A component
15- 20 F6.2 deg SepA Position Angle to A component
22 A1 --- Phot? [PYN] Information about the stability of the
atmosphere for the observations (according to
the acquisition date)
24- 28 F5.2 mag imag ?=- SDSS i magnitude
30- 33 F4.2 mag e_imag ? rms uncertainty on imag
35- 39 F5.2 mag zmag ?=- SDSS z magnitude (2)
41- 44 F4.2 mag e_zmag ? rms uncertainty on zmag
46- 49 F4.2 mag Dimag ?=- Relative i magnitude to A component
51- 54 F4.2 mag e_Dimag ? rms uncertainty on Dimag
56- 59 F4.2 mag Dzmag ?=- Relative z magnitude to A component
61- 64 F4.2 mag e_Dzmag ? rms uncertainty on Dzmag
66- 72 F7.4 mag (i-z) ?=- SDSS i-z colour index
74- 78 F5.3 mag e_(i-z) ? rms uncertainty on (i-z)
80- 83 F4.2 mag s_(i-z) ?=- Photometric error if we were to take into
account the empirical errors in the software
gain of the instrument (only in table5)
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Note (1): Notes as follows:
* = Object assumed to be the Kepler object of interest. In the case
of close companions with similar magnitudes, it is difficult to
distinguish which is the actual host. The assumed KOI is the
brightest object in the system.
+ = Companion probably bound according to Sect. 4.2.2.
Note (2): For table6, Only objects with additional companions within
3arcsec have magnitudes in the SDSSz. KOI-0372 also has this
information because during the observing run it had seemed to have
a close companion that, however, after the reduction was discarded.
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Byte-by-byte Description of file: table7.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- KOI [99/1574] KOI number
6 A1 --- m_KOI [ABC] Component
8- 17 F10.6 deg RAdeg Right ascension (J2000) (1)
19- 28 F10.6 deg DEdeg Declination (J2000) (1)
30- 35 F6.1 K Teff Effective temperature
37- 39 F3.1 [cm/s2] logg Surface gravity
41- 45 F5.2 --- chi2 chi2 value
47- 49 A3 --- SpType MK spectral type
51- 57 A7 --- Model Best fit model used by VOSA (2)
59- 63 I5 pc Dist ? Distance
65- 68 I4 pc E_Dist ? Error on Dist (upper value)
70- 73 I4 pc e_Dist ? Error on Dist (lower value)
74 A1 --- f_Dist [cd] Problematic cases (3)
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Note (1): Calculated RA, DE from the position of the KOI according to the
distance and angle derived in this paper
Note (2): See http://svo.cab.inta-csic.es/theory/vosa/ for more information.
Note (3): Notes as follows:
c = Effective temperature is outside the model range
d = Estimated distance is greater than 21kpc (the estimated Milky Way
limit in the Kepler line of sight)
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Byte-by-byte Description of file: table8.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- KOI [99/1574] KOI number (2)
5 A1 --- --- [.]
6- 7 I02 --- Pl [01/03] Planet candidate (2)
9- 13 I5 10-6 depth.c Catalog planet-transit depth (in ppm)
15- 19 I5 10-6 depth New planet-transit depth (in ppm)
21- 23 I3 10-6 e_depth rms uncertainty on depth (in ppm)
25- 29 F5.2 10-2 Rp/R*.c Catalog planet-to-star radii ratio
31- 34 F4.2 10-2 e_Rp/R*.c rms uncertainty on Rp/R*.c
36- 41 F6.3 10-2 Rp/R* New planet-to-star radii ratio assuming no
limb-darkening
43- 47 F5.3 10-2 e_Rp/R* rms uncertainty on Rp/R*
49- 52 F4.1 10-2 Rp/R*.2 Planet-to-star radius assuming that the host
is actually the secondary companion detected
at less than 3 arcsec
54- 57 F4.1 10-2 e_Rp/R*.2 rms uncertainty on Rp/R*.2
59- 63 F5.2 Rgeo Rp.c Planet radii calculated by the Kepler team
(Batalha et al., 2012, ApJS, submitted)
65- 69 F5.2 Rgeo Rp Planet radii assuming the new depth and no
limb-darkening (1)
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Note (1): No error is presented since no error in the stellar radii is given.
Note (2): the KOI planet candidate is NNNN.nn, where NNNN is the KOI number
and nn the planet candidate number
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 03-Dec-2012