J/AJ/150/178 Minima of 41 binaries from entire Kepler mission (Gies+, 2015)
Kepler eclipsing binaries with stellar companions.
Gies D.R., Matson R.A., Guo Z., Lester K.V., Orosz J.A., Peters G.J.
<Astron. J., 150, 178 (2015)>
=2015AJ....150..178G 2015AJ....150..178G (SIMBAD/NED BibCode)
ADC_Keywords: Stars, variable ; Binaries, eclipsing
Keywords: binaries: close - binaries: eclipsing - stars: formation - starspots -
techniques: photometric
Abstract:
Many short-period binary stars have distant orbiting companions that
have played a role in driving the binary components into close
separation. Indirect detection of a tertiary star is possible by
measuring apparent changes in eclipse times of eclipsing binaries as
the binary orbits the common center of mass. Here we present an
analysis of the eclipse timings of 41 eclipsing binaries observed
throughout the NASA Kepler mission of long duration and precise
photometry. This subset of binaries is characterized by relatively
deep and frequent eclipses of both stellar components. We present
preliminary orbital elements for seven probable triple stars among
this sample, and we discuss apparent period changes in seven
additional eclipsing binaries that may be related to motion about a
tertiary in a long period orbit. The results will be used in ongoing
investigations of the spectra and light curves of these binaries for
further evidence of the presence of third stars. Fundamental
Parameters
Description:
We embarked on a search for eclipse timing variations among a subset
of 41 eclipsing binaries that were identified prior to the start of
Kepler observations (see our first paper, Gies et al. 2012, cat.
J/AJ/143/137). Our first paper documented the eclipse times in
observations made over quarters Q0-Q9 (2009.3-2011.5). Now with the
Kepler mission complete with observations through Q17 (ending 2013.4),
we present here the eclipse timings for our sample of 41 binaries over
the entire duration of the mission.
The associated times given in our first paper were based upon UTC
(Coordinated Universal Time) while the current set uses TDB
(Barycentric Dynamical Time), and here we report the times in reduced
Barycentric Julian Date (BJD-2400000 days). We used the Simple
Aperture Photometry (SAP) flux except in the case of KIC04678873. The
list of targets appears in Table1.
The eclipse timing measurements were made in almost the same way as
described in our first paper. Our measurements appear in Table2.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 92 82 Eclipsing binary properties
table2.dat 44 55860 Eclipse timing measurements
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See also:
B/gcvs : General Catalogue of Variable Stars (Samus+ 2007-2013)
V/133 : Kepler Input Catalog (Kepler Mission Team, 2009)
V/118 : Catalog of eclipsing binaries parameters (Perevozkina+, 1999)
J/A+A/579/A19 : K2 Variable Catalogue (Armstrong+, 2015)
J/MNRAS/452/3561 : Kepler eclipsing binary stars (LaCourse+, 2015)
J/AJ/149/197 : Minima of 10 Kepler eclipsing binaries (Zasche+, 2015)
J/AJ/149/93 : Eclipse timings of KIC 5621294 (Lee+, 2015)
J/AJ/147/45 : Kepler mission. IV. (Conroy+, 2014)
J/AJ/143/137 : Minima of 41 eclipsing binaries from a Kepler survey
(Gies+, 2012)
J/AJ/142/160 : Kepler Mission. II. eclipsing binaries (Slawson+, 2011)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 8 I8 --- KIC Kepler Input Catalog number
9 A1 --- f_KIC [PS] Primary (deeper) or secondary eclipse
11- 15 F5.1 s Ierr Average uncertainty in eclipse time
measurement (internal scatter)
17- 21 F5.1 s Eerr Standard deviation of the full set of
measurements (external scatter)
23- 34 F12.6 d T0 Epoch of minimum near the middle to the time
series (reduced Barycentric Julian Date;
BJD-2400000)
36- 38 I3 10-6d e_T0 Uncertainty in T0
40- 50 F11.9 d Per Orbital period
52- 55 I4 10-9d e_Per Uncertainty in Per
57- 64 F8.4 10-6/yr Pvar Period derivative Pdot/P (1)
66- 70 I5 10-10/yr e_Pvar Uncertainty in Pvar
72- 76 F5.3 --- sDE Standard deviation of the eclipse depth factor
σ(DE)
78- 92 A15 --- Ref Reference code on eclipse timing for the
target (2)
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Note (1): Pdot/P=2Q/P2 (Eq. (3) in the paper).
Note (2): Reference code defined as follows:
C14 = Conroy et al. 2014 (cat. J/AJ/147/45);
H13 = Hambleton et al. (2013MNRAS.434..925H 2013MNRAS.434..925H);
L15 = Lee et al. 2015 (cat. J/AJ/149/93);
O15 = Orosz (2015ASPC..496...55O 2015ASPC..496...55O);
Z15 = Zasche et al. 2015 (cat. J/AJ/149/197);
ECC = Non-zero eccentricity, as indicated by significantly differing epochs
of eclipse, (|T(sec)-T(pri)-P/2|modP)>0.
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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- 8 I8 --- KIC [2305372/12071006] Kepler Input Catalog number
10 I1 --- Type [1/2] Eclipse type (1=primary, 2=secondary)
12- 24 F13.5 d TE Barycentric Julian Date of eclipse (1)
26- 32 F7.5 d e_TE Uncertainty in TE σ(TE)
34- 38 F5.3 --- DE [0.6/1.5] Eclipse depth scaling factor DE (2)
40- 44 F5.3 --- e_DE [0/0.13] Uncertainty in DE σ(TE)
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Note (1): TE=T+PE+QE2 (Eq. (2) in the paper), where E is the integer eclipse
cycle number in the time series.
Note (2): This parameter allows the eclipse template to be transformed by:
F(revised)=1-DE+DEF(template) (Eq. (1) in the paper),
so that temporal changes in the eclipse depth may be tracked. The eclipse
depth changes are interesting in the context of long term changes (due to
apsidal motion for example), starspot activity, and quarter-to-quarter
blending of the target flux with that from stars with small angular
separations. Please refer to Section 2 in the paper for additional details.
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History:
From electronic version of the journal
(End) Prepared by [AAS]; Sylvain Guehenneux [CDS] 28-Jun-2016