J/AJ/158/58 Autoregressive planet search for Kepler stars (Caceres+, 2019)
Autoregressive planet search: application to the Kepler mission.
Caceres G.A., Feigelson E.D., Babu G.J., Bahamonde N., Christen A.,
Bertin K., Meza C., Cure M.
<Astron. J., 158, 58 (2019)>
=2019AJ....158...58C 2019AJ....158...58C (SIMBAD/NED BibCode)
ADC_Keywords: Stars, double and multiple ; Exoplanets ; Magnitudes ; Models
Keywords: methods: statistical - planets and satellites: detection -
planets and satellites: terrestrial planets
Abstract:
The 4 yr light curves of 156717 stars observed with NASA's Kepler mission
are analyzed using the autoregressive planet search (ARPS) methodology
described by Caceres et al. (2019AJ....158...57C 2019AJ....158...57C). The three stages of
processing are maximum-likelihood ARIMA modeling of the light curves
to reduce stellar brightness variations, constructing the transit comb
filter periodogram to identify transit-like periodic dips in the ARIMA
residuals, and Random Forest classification trained on Kepler team
confirmed planets using several dozen features from the analysis. Orbital
periods between 0.2 and 100 days are examined. The result is a recovery
of 76% of confirmed planets, 97% when period and transit depth constraints
are added. The classifier is then applied to the full Kepler data set;
1004 previously noticed and 97 new stars have light-curve criteria
consistent with the confirmed planets, after subjective vetting removes
clear false alarms and false positive cases. The 97 Kepler ARPS candidate
transits mostly have periods of P<10 days; many are ultrashort period
hot planets with radii <1% of the host star. Extensive tabular and
graphical output from the ARPS time series analysis is provided to assist
in other research relating to the Kepler sample.
Description:
The ARPS methodology is applied to long-cadence photometry from the prime
phase of NASA's Kepler mission (Borucki et al. 2010Sci...327..977B 2010Sci...327..977B). The
data set used in the ARPS analysis here is long-cadence light curve data
from Data Release 25 (DR25) for Quarters 1 through 17 obtained in 2016
April from the Kepler Data Products residing at NASA's Mikulski Archive
for Space Telescopes (MAST). Each light curve records ∼70000 measurements
of stellar flux in a regularly spaced cadence of 29.4 minutes, measured
in instrumental units of electrons per second continuously for about 4 yr.
Many stars are not observed for the full 17 three month quarters and
thereby exhibit long gaps in the data stream. All stars show gaps for
a variety of instrumental causes totaling 15% or more of the data stream.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 236 156717 ARPS results for the full Kepler dataset
table5.dat 65 97 Kepler ARPS candidate transits
notes.dat 639 97 Notes on individual objects in Table 5
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See also:
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
V/133 : Kepler Input Catalog (Kepler Mission Team, 2009)
J/ApJS/199/24 : The first three quarters of Kepler mission
(Tenenbaum+, 2012)
J/A+A/555/A58 : New Kepler planetary candidates (Ofir+, 2013)
J/MNRAS/429/2001 : New transiting planet candidates from Kepler (Huang+, 2013)
J/ApJ/784/45 : Kepler's multiple planet candidates. III. (Rowe+, 2014)
J/ApJ/787/47 : 106 Kepler ultra-short-period planets (Sanchis-Ojeda+, 2014)
J/ApJS/210/19 : Kepler planetary candidates. IV. 22 months (Burke+, 2014)
J/ApJS/217/16 : Kepler planetary candidates. V. 3yr Q1-Q12 (Rowe+, 2015)
J/ApJS/217/18 : Potential transit signals in Kepler Q1-Q17 (Seader+, 2015)
J/ApJS/217/31 : Kepler planetary candidates. VI. 4yr Q1-Q16
(Mullally+, 2015)
J/AJ/151/68 : Kepler Mission. VII. Eclipsing binaries in DR3 (Kirk+, 2016)
J/AJ/152/158 : Final Kepler transiting planet search (DR25)
(Twicken+, 2016)
J/ApJS/224/12 : Kepler planetary candidates. VII. 48-month (Coughlin+, 2016)
J/ApJS/235/38 : Kepler planetary cand. VIII. DR25 reliability
(Thompson+, 2018)
J/AJ/158/59 : Autoregressive planet search: irregular time series
(Stuhr+, 2019)
Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 8 I8 --- KIC [757076/12688631] Kepler Input Catalog identifier
10- 15 F6.3 mag Kepmag [5.995/20.762] Kepler magnitude
17- 33 A17 --- Quarters Quarters observed; 1-17
35- 43 A9 --- KOI Kepler Object of Interest name (KONNNN.NN)
45- 58 A14 --- Kepler KOI additional name
60- 63 A4 --- Disp KOI disposition (1)
65- 78 F14.7 d PerKOI [0.2418425/129995.7784]? KOI transit period
80- 88 F9.1 ppm DepthKOI [5.9/1541400]? KOI transit depth
90- 96 F7.1 --- S/N-KOI [0.5/14860.3]? KOI model signal-to-noise ratio
98-109 F12.7 d PerKEBC [0.0737309/1087.3]? Period if listed in the
Kepler Eclipsing Binary Catalog (Kirk et al.
2016, J/AJ/151/68)
111-114 F4.2 --- LC-NA [0.07/0.99]? Fraction of 4 yr time slots with
"Not Available" entries
116-124 I9 e/s LC-Med [-34/98616280] Median pre-search data
conditioning (PDC) flux
126-134 F9.1 e/s LC-IQR [2.7/5121316.8] InterQuartile Range (IQR) of
stitched light curve
136-143 F8.1 e/s LC-dIQR [3.9/90609.4] IQR of differenced lightcurve
145-147 I3 --- AR-Mod [0/512] ARIMA model order; p,d,q (2)
149-156 F8.1 e/s AR-IQR [3/55505.6] IQR of ARIMA residual
158-160 I3 --- ARF-Mod [10/515] ARFIMA model order; p,d,q (2)
162-165 F4.2 --- ARF-d [1/1.5] ARFIMA fractional differencing order (3)
167-173 F7.1 e/s ARF-IQR [0/31142.4] IQR of ARFIMA residual
175-183 F9.6 d PerTCF [0.204336/99.998713] Transit Comb Filter (TCF)
period
185-193 F9.1 --- TCF-Pow [25.2/8.63975e+06]?=9999999 TCF power
195-200 F6.1 --- TCF-S/N [3.1/9983.9]?=9999 TCF signal-to-noise ratio
after subtraction of LOESS trend curve
202-207 F6.1 --- TCF-Shp [-1.3/3472.6]?=9999 TCF shape statistic (4)
209-217 F9.1 e/s TCF-Dep [-100000/6.03108e+06]?=9999999 TCF depth
219-222 I4 --- TCF-Pha [1/4842] TCF phase; 29.4 minutes cadence
224-226 I3 --- TCF-Dur [1/50] TCF duration; 29.4 minutes cadence
228-230 I3 --- TCF-Har [-1/2]? TCF harmonics indicator (G1)
232-236 F5.3 --- RF-Prob [0/0.997] Random Forest probability for exoplanet
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Note (1): KOI disposition as follows:
CAND = Candidate;
FP = False Positive.
Note (2): The AR-Mod and ARF-Mod values represent the order of the
autoregressive models. A value like 400 represents (p,d,q)=(4,1,0) where d is
increased by 1 due to an earlier differencing operation.
Note (3): The value ARF-d for the ARFIMA model quantifies 1/fα
long-memory red noise: d=1 implies α=0.
Note (4): High values indicate low-duty cycle periodic behaviors.
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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 I2 --- KACT [1/97] Kepler ARPS Candidate Transits (1)
4- 11 I8 --- KIC [1701672/12070798] Kepler Input Catalog
13- 28 A16 --- 2MASS 2MASS star designation (HHMMSSss+DDMMSSs)
30- 34 F5.2 mag Kepmag [12.09/17.56] Kepler magnitude
36- 44 F9.6 d Per [0.207054/42.03793] Transit period
46- 49 I4 ppm Depth [19/1250] Transit depth
51- 55 F5.1 --- TCF-S/N [12.3/175.3] TCF periodogram peak signal-to-noise
ratio
57- 58 I2 --- TCF-Har [-1/2]? TCF periodogram peak harmonics indicator
(G1)
60- 63 F4.2 --- RF-Prob [0.35/0.77] Random Forest classification
probability
65 I1 --- USP [0/1]? UltraShort Period (USP) indicator (2)
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Note (1): See notes.dat file for notes on individual objects.
Note (2): UltraShort Period indicator as follows:
0 = Period>1.0 d;
1 = Period<1.0 d.
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Byte-by-byte Description of file: notes.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- KACT [1/97] Kepler ARPS Candidate Transits
4-639 A636 --- Note Comment on KACT
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Global notes:
Note (G1): TCF harmonics indicator as follows:
0 = No harmonic;
-1 = Half-period harmonic;
1 = Twice-period harmonic;
2 = Both half- and twice-period harmonic.
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History:
From electronic version of the journal
References:
Feigelson et al. Paper I. 2019AJ....158...57C 2019AJ....158...57C
Stuhr et al. Paper III. 2019AJ....158...59S 2019AJ....158...59S, Cat. J/AJ/158/59
(End) Prepared by [AAS], Tiphaine Pouvreau [CDS] 20-Sep-2019