J/AJ/162/84 Searching for Small Circumbinary Planets. I. STANLEY (Martin+, 2021)
Searching for Small Circumbinary Planets.
I. The STANLEY Automated Algorithm and No New Planets in Existing Systems.
Martin D.V., Fabrycky D.C.
<Astron. J., 162, 84 (2021)>
=2021AJ....162...84M 2021AJ....162...84M
ADC_Keywords: Exoplanets; Stars, double and multiple; Binaries, eclipsing
Keywords: Eclipsing binary stars ; Exoplanet detection methods ;
Transit timing variation method ; Transit duration variation method ;
Extrasolar rocky planets ; N-body simulations
Abstract:
No circumbinary planets have been discovered smaller than 3R⊕,
yet planets of this small size comprise over 75% of the discoveries
around single stars. The observations do not prove the nonexistence of
small circumbinary planets; rather, they are much harder to find than
around single stars because their transit timing variations are much
larger than the transit durations. We present Stanley, an automated
algorithm to find small circumbinary planets. It employs custom
methods to detrend eclipsing binary light curves and stack shallow
transits of variable duration and interval using N-body integrations.
Applied to the Kepler circumbinaries, we recover all known planets,
including the three planets of Kepler-47, and constrain the absence of
additional planets of similar or smaller size. We also show that we
could have detected <3R⊕ planets in half of the known systems.
Our work will ultimately be applied to a broad sample of eclipsing
binaries to (hopefully) produce new discoveries and derive a
circumbinary size distribution that can be compared to that for single
stars.
Description:
Cross talk between different Kepler pixels is an instrumental defect
that can make transit-like signatures appear in multiple different
targets (not just binaries) at the same time. To find such events, we
ran the detrending algorithm on 270 of the binaries from the Windemuth
catalog (Windemuth+, 2019MNRAS.489.1644W 2019MNRAS.489.1644W), with cuts made to only
include binaries between 7 and 50 day periods. For each binary, we
output the times corresponding to the nine points of lowest flux,
where we avoided listing multiple times within a 1 day bin. We then
created a histogram of the deepest points across all of these
binaries, using day-wide bins.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
fig5.dat 13 34 *Common false positive times
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Note on fig5.dat : This is a list of 34 times (BJD-2455000) that we
suspect correspond to false positive flux dips in Kepler eclipsing
binary lightcurves. They were discovered by running the detrending
algorithm on a sample of 270 eclipsing binaries, selecting the nine
deepest flux points for each binary, and then finding which times were
discovered in more than 5/270 binaries. The exact cut start and end
times were made by hand, making sure to remove all spurious low flux
points.
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See also:
J/AJ/141/83 : Kepler Mission. I. Eclipsing binaries in DR1 (Prsa+, 2011)
J/other/Sci/337.1511 : Kepler-47 transits (Orosz+, 2012)
J/ApJ/761/123 : KELT-1 photometry and spectroscopy follow-up (Siverd+, 2012)
J/other/Nat/481.475 : Rvel of Kepler-34b & Kepler-35b (Welsh+, 2012)
J/ApJ/768/127 : Q1-11 Kepler light curve of KIC 4862625 (Schwamb+, 2013)
J/A+A/561/A138 : Transiting planets Matlab/Octave source code (Ofir+, 2014)
J/ApJ/807/45 : Habitable planets orbiting M dwarfs (Dressing+, 2015)
J/AJ/151/68 : Kepler Mission. VII. Eclipsing binaries in DR3 (Kirk+, 2016)
J/AJ/154/109 : California-Kepler Survey. III. Planet radii (Fulton+, 2017)
J/A+A/602/A117 : Periods of 2290 CoRoT binaries (Klagyivik+, 2017)
J/AJ/154/216 : Rvel of 41 Kepler eclipsing binaries (Matson+, 2017)
J/AJ/156/78 : 44 validated planets from K2 Campaign 10 (Livingston+, 2018)
J/AJ/157/174 : Transiting planets in Kepler-47 circumb. system (Orosz+, 2019)
Byte-by-byte Description of file: fig5.dat
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Bytes Format Units Label Explanations
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1- 6 F6.1 d Start [-18.6/1142] Starting data of the cut
8- 13 F6.1 d End [-18.2/1143] Ending data of the cut
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History:
From electronic version of the journal
(End) Prepared by [AAS], Coralie Fix [CDS], 24-Nov-2021