J/ApJS/244/11 Planet candidates and EBs in K2 campaigns 0-8 (Kruse+, 2019)
Detection of hundreds of new planet candidates and eclipsing binaries in
K2 campaigns 0-8.
Kruse E., Agol E., Luger R., Foreman-Mackey D.
<Astrophys. J. Suppl. Ser., 244, 11-11 (2019)>
=2019ApJS..244...11K 2019ApJS..244...11K (SIMBAD/NED BibCode)
ADC_Keywords: Exoplanets; Binaries, eclipsing; Stars, diameters
Keywords: Eclipsing binary stars; Transit photometry; Light curves
Exoplanet catalogs; Transit timing variation method; Exoplanets
Exoplanet systems; Exoplanet detection methods
Abstract:
We implement a search for exoplanets in campaigns zero through eight
(C0-8) of the K2 extension of the Kepler spacecraft. We apply a
modified version of the Quasi-periodic Automated Transit Search (QATS)
planet search algorithm to K2 light curves produced by the EVEREST
pipeline, carrying out the C0-8 search on 1.5x105 target stars with
magnitudes in the range of Kp=9-15. We detect 818 transiting planet
candidates, of which 374 were undiscovered by prior searches, with
{64, 15, 5, 2, 1} in {2, 3, 4, 5, 6}-planet multiplanet candidate
systems, respectively. Of the new planets detected, 100 orbit M
dwarfs, including one that is potentially rocky and in the habitable
zone. A total of 154 of our candidates reciprocally transit with our
solar system: they are geometrically aligned to see at least one solar
system planet transit. We find candidates that display transit timing
variations and dozens of candidates on both period extremes with
single transits or ultrashort periods. We point to evidence that our
candidates display similar patterns in frequency and size-period
relation to confirmed planets, such as tentative evidence for the
radius gap. Confirmation of these planet candidates with follow-up
studies will increase the number of K2 planets by up to 50%, and
characterization of their host stars will improve statistical studies
of planet properties. Our sample includes many planets orbiting bright
stars amenable for radial velocity follow-up and future
characterization with JWST. We also list the 579 eclipsing binary
systems detected as part of this search.
Description:
We have presented a comprehensive update to the Carter & Agol
(2013ApJ...765..132C 2013ApJ...765..132C) QATS transit detection pipeline with the goal of
developing it into a nearly all-encompassing transit search that can
find periodic planets, those with TTVs, single-transit events, and
ultra-short-period planets--all without losing sensitivity to the
lowest-S/N planets or multiplanet systems. We applied this method to
152865 stars in K2 campaigns 0-8 (2014 March-2016 Jan), using the
light curves from EVEREST 1.0 (Section 2). In total, we found 818
planet candidates, 374 of which are new and undetected by all previous
searches (Section 3.3); we also presented our catalog of 579 eclipsing
binaries (EBs) detected as part of this search (Section 3.5).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
stars.dat 9 1276 EPIC stars listed in Tables 7 and 9;
table added by CDS
table7.dat 244 818 Our sample of planet candidates from C0-8
table9.dat 129 1060 Our sample of eclipsing binaries from C0-8
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See also:
IV/34 : K2 Ecliptic Plane Input Catalog (EPIC) (Huber+, 2017)
J/ApJS/197/8 : Kepler's candidate mult. transiting planets (Lissauer+, 2011)
J/ApJ/767/95 : Improved stellar param. of smallest KIC stars (Dressing+, 2013)
J/ApJS/208/16 : Kepler transit timing observations. VIII. (Mazeh+, 2013)
J/ApJS/210/20 : Small Kepler planets radial velocities (Marcy+, 2014)
J/ApJ/784/45 : Kepler's multiple planet candidates. III. (Rowe+, 2014)
J/AJ/147/119 : Cat. of sources in the Kepler field of view (Coughlin+, 2014)
J/ApJ/787/47 : 106 Kepler ultra-short-period planets (Sanchis-Ojeda+, 2014)
J/ApJ/790/146 : Planets in Kepler's multi-transiting systems (Fabrycky+, 2014)
J/ApJ/807/45 : Potentially habitable planets around M dwarfs (Dressing+, 2015)
J/ApJ/809/25 : Stellar and planet properties for K2 candidates (Montet+, 2015)
J/ApJS/222/14 : Planetary candidates from 1st yr K2 mission (Vanderburg+, 2016)
J/AJ/151/68 : Kepler Mission. VII. Eclipsing binaries in DR3 (Kirk+, 2016)
J/ApJS/224/2 : K2 EPIC stellar properties for 138600 targets (Huber+, 2016)
J/ApJS/224/12 : Kepler planetary candidates. VII. 48-month (Coughlin+, 2016)
J/ApJS/226/7 : Planet cand. discovered using K2's 1st yr (Crossfield+, 2016)
J/A+A/594/A100 : K2 new planetary and EB candidates (Barros+, 2016)
J/AJ/152/105 : Kepler-80 transit timing observations (MacDonald+, 2016)
J/MNRAS/463/1780 : Exoplanet candidates in Praesepe (M 44) (Libralato+, 2016)
J/MNRAS/463/1831 : M67 Kepler/K2 variable stars (Nardiello+, 2016)
J/ApJ/836/167 : K2 planetary syst. around low-mass stars. I. (Dressing+, 2017)
J/AJ/154/109 : California-Kepler Survey (CKS). III. Radii (Fulton+, 2017)
J/AJ/154/207 : K2 planetary systems orbiting low-mass stars (Dressing+, 2017)
J/AJ/155/21 : Planet candidates from K2 campaigns 5-8 (Petigura+, 2018)
J/AJ/155/136 : Planets around bright stars in K2 campaigns 0-10 (Mayo+, 2018)
J/ApJS/235/38 : Kepler planetary cand. VIII. DR25 reliability (Thompson+, 2018)
J/AJ/156/89 : RVs + transit-times for the K2-24 systems (Petigura+, 2018)
J/AJ/156/277 : 60 validated planets from K2 campaigns 5-8 (Livingston+, 2018)
http://keplerscience.arc.nasa.gov/ : Kepler & K2 science center home page
http://exoplanetarchive.ipac.caltech.edu/ : NASA exoplanet archive
Byte-by-byte Description of file: stars.dat
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Bytes Format Units Label Explanations
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1- 9 I9 --- EPIC [201147085/229228348] K2 Input Catalog ID
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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- 9 I9 --- EPIC [201147085/229228348] K2 Input Catalog ID
10 A1 --- --- [.]
11 I1 --- m_EPIC [1/6] Planet candidate identifier
within EPIC number
13- 13 I1 --- C [0/8] Campaign number
15- 25 F11.8 d Per [0.2/64]? Period
27- 36 F10.8 d E_Per [6.3e-7/0.04]? Upper uncertainty in Per
38- 47 F10.8 d e_Per [6.3e-7/0.05]? Lower uncertainty in Per
49- 59 F11.6 d t0 Barycentric Julian Date of mid-transit time;
BJD-2455000
61- 68 F8.6 d E_t0 [2.3e-5/0.03] Upper uncertainty in t0
70- 77 F8.6 d e_t0 [2.3e-5/0.03] Lower uncertainty in t0
79- 85 F7.4 h Dur [0.4/23] Transit duration
87- 92 F6.4 h E_Dur [0.005/1.4] Upper uncertainty in Dur
94- 99 F6.4 h e_Dur [0.004/1.5] Lower uncertainty in Dur
101-107 F7.1 ppm Depth [56/39600] Transit depth
109-115 F7.1 ppm E_Depth [3/10200] Upper uncertainty in Depth
117-122 F6.1 ppm e_Depth [3/6300] Lower uncertainty in Depth
124-130 F7.5 --- Rp/R* [0.007/0.5] Ratio of planetary to stellar radii
132-138 F7.5 --- E_Rp/R* [0.0002/0.2] Upper uncertainty in Rp/R*
140-146 F7.5 --- e_Rp/R* [0.0006/0.2] Lower uncertainty in Rp/R*
148-155 F8.3 Rgeo Rp [0.4/1080]? Planet radius
157-163 F7.3 Rgeo E_Rp [0.04/320]? Upper uncertainty in Rp
165-171 F7.3 Rgeo e_Rp [0.1/350]? Lower uncertainty in Rp
173-179 F7.4 Rsun R* [0.1/85]? Stellar radius
181-187 F7.4 Rsun E_R* [0.002/18]? Upper uncertainty in R*
189-195 F7.4 Rsun e_R* [0.002/25]? Lower uncertainty in R*
197-203 F7.3 --- a/R* [1/130]? Semi-major axis to stellar radius ratio
205-210 F6.3 --- E_a/R* [0.01/45]? Uncertainty in a/R*
212-217 F6.3 --- e_a/R* [0.01/84]? Uncertainty in a/R*
219-226 F8.2 Earth Sinc [0.5/94000]? Incident flux; in Earth units
228-235 F8.2 Earth E_Sinc [0.3/27000]? Upper uncertainty in Sinc
237-244 F8.2 Earth e_Sinc [0.2/60000]? Lower uncertainty in Sinc
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Byte-by-byte Description of file: table9.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 I9 --- EPIC [201160323/220732672] K2 Input Catalog ID
10 A1 --- --- [.]
11 I1 --- m_EPIC [1/3] Binary identifier within EPIC number
13- 13 I1 --- C [0/8] Campaign number
15- 25 F11.8 d Per [0.2/73]? Period
27- 36 F10.8 d E_Per [2.4e-7/0.02]? Upper uncertainty in Per
38- 47 F10.8 d e_Per [2.4e-7/0.02]? Lower uncertainty in Per
49- 60 F12.7 d t0 Barycentric Julian Date of mid-transit time;
BJD-2455000
62- 70 F9.7 d E_t0 Upper uncertainty in t0
72- 80 F9.7 d e_t0 Lower uncertainty in t0
82- 88 F7.4 h Dur [0.03/32.1] Eclipse duration
90- 95 F6.4 h E_Dur [0.002/2.7] Upper uncertainty in Dur
97-102 F6.4 h e_Dur [0.002/4.1] Lower uncertainty in Dur
104-111 F8.1 ppm Depth [89/999958] Eclipse depth
113-120 F8.1 ppm E_Depth [6/580000] Upper uncertainty in Depth
122-129 F8.1 ppm e_Depth [7/139000] Lower uncertainty in Depth
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 11-Feb-2020