J/AJ/158/59 Autoregressive planet search: irregular time series (Stuhr+, 2019)
Autoregressive planet search: feasibility study for irregular time series.
Stuhr A.M., Feigelson E.D., Caceres G.A., Hartman J.D.
<Astron. J., 158, 59 (2019)>
=2019AJ....158...59S 2019AJ....158...59S (SIMBAD/NED BibCode)
ADC_Keywords: Stars, variable ; Exoplanets ; Photometry ; Models
Keywords: methods: statistical - planets and satellites: detection -
stars: variables: general - techniques: photometric
Abstract:
Sensitive signal processing methods are needed to detect transiting planets
from ground-based photometric surveys. Caceres et al. (2019AJ....158...58C 2019AJ....158...58C)
show that the autoregressive planet search (ARPS) method - a combination
of autoregressive integrated moving average (ARIMA) parametric modeling,
a new transit comb filter (TCF) periodogram, and machine learning
classification - is effective when applied to evenly spaced light curves
from space-based missions. We investigate here whether ARIMA and TCF will
be effective for ground-based survey light curves that are often sparsely
sampled with high noise levels from atmospheric and instrumental
conditions. The ARPS procedure is applied to selected light curves with
strong planetary signals from the Kepler mission that have been altered
to simulate the conditions of ground-based exoplanet surveys. Typical
irregular cadence patterns are used from the Hungarian-made Automated
Telescope Network-South (HATSouth) survey. We also evaluate recovery
of known planets from HATSouth. Simulations test transit signal recovery
as a function of cadence pattern and duration, stellar magnitude, planet
orbital period, and transit depth. Detection rates improve for shorter
periods and deeper transits. The study predicts that the ARPS methodology
will detect planets with ≳0.1% transit depth and periods ~<40 days in
HATSouth stars brighter than ∼15 mag. ARPS methodology is therefore
promising for planet discovery from ground-based exoplanet surveys with
sufficiently dense cadence patterns.
Description:
Two data sets are used for the analysis here: stars with unusually
deep transits in NASA's four-year Kepler mission (Borucki et al.
2010Sci...327..977B 2010Sci...327..977B), and stars with confirmed transits from the HATnet
HATSouth survey (HATS; Bakos et al. 2013PASP..125..154B 2013PASP..125..154B). The Kepler data
are long-cadence light curves from Data Release 25 for Quarters 1 through
17 obtained from the Kepler Data Products residing at NASA's Mikulski
Archive for Space Telescopes (MAST) with the final catalog provided by
Thompson et al. (2018, J/ApJS/235/38). The HATSouth survey (Bakos et al.
2013PASP..125..154B 2013PASP..125..154B) uses six telescope units to conduct wide-field
photometric time-series observations of the sky in search of transiting
exoplanets. The telescopes are located at three observatories in the
southern hemisphere (Las Campanas Observatory in Chile, LCO; the HESS
gamma-ray telescope site in Namibia, HESS; and Siding Spring Observatory
in Australia, SSO) with two telescope units at each site.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 88 19 Kepler stars with deep transits
table2.dat 77 34 HATSouth stars with confirmed planets
table3.dat 61 210 Transit comb filter (TCF) periodogram S/N ratios
for simulated ground-based observations of
19 Kepler planets
table4.dat 39 22 Success rate of detecting Kepler planets
using HATSouth cadences
table6.dat 33 34 HATSouth planets and their corresponding TCF S/N
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See also:
V/133 : Kepler Input Catalog (Kepler Mission Team, 2009)
J/A+A/558/A55 : HATS-2b griz light curves (Mohler-Fischer+, 2013)
J/AJ/145/5 : Follow-up photometry of HATS-1 (Penev+, 2013)
J/AJ/146/113 : Differential griz photometry of HATS-3 (Bayliss+, 2013)
J/AJ/147/144 : Differential griz photometry of HATS-5 (Zhou+, 2014)
J/AJ/148/29 : Spectroscopy and differential photometry of HATS-4
(Jordan+, 2014)
J/A+A/580/A63 : HATS-13b and HATS-14b light and RV curves (Mancini+, 2015)
J/AJ/149/166 : Photometry and spectroscopy of HATS-6 (Hartman+, 2015)
J/AJ/150/33 : Photometry and spectroscopy of HATS-9 and HATS-10
(Brahm+, 2015)
J/AJ/150/49 : Photometry and spectroscopy of HATS-8 (Bayliss+, 2015)
J/ApJ/813/111 : Differential photometry of the K dwarf HATS-7 (Bakos+, 2015)
J/AJ/151/89 : Spectroscopy and photometry of HATS-17 (Brahm+, 2016)
J/AJ/152/88 : Spectroscopy and photometry of HATS-11 and HATS-12
(Rabus+, 2016)
J/AJ/152/108 : i filter photometry for HATS-25 through HATS-30
(Espinoza+, 2016)
J/AJ/152/127 : Sloan i follow-up light curves of HATS-18 (Penev+, 2016)
J/AJ/152/161 : Photometry for HATS-31 through HATS-35 (de Val-Borro+, 2016)
J/ApJS/235/38 : Kepler planetary cand. VIII. DR25 reliability (Thompson+, 2018)
J/AJ/158/58 : Autoregressive planet search for Kepler stars (Caceres+, 2019)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 I9 --- KIC [757450/11804465]? Kepler Input Catalog
designation
11- 21 A11 -- Kepler Kepler planet name
23- 43 A21 --- Disc Discovery reference
45- 63 A19 --- Bibcode Bibcode of the reference
65- 70 F6.3 d Per [1.486/41.408]? Orbital period
72- 76 F5.2 mmag Depth [5.57/36.9]? Transit depth
78- 82 F5.2 mag Kepmag [10.46/16.88]? Kepler magnitude
84 A1 --- l_Thres [>] Limit flag on Thres
85- 88 F4.1 mag Thres [13.3/16]? Threshold magnitude (1)
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Note (1): The magnitude where transit comb filter (TCF) S/N drops below 20,
setting a rough threshold for detectability.
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 A9 --- Planet Planet name (HATS-NNa)
11- 38 A28 --- Disc Discovery reference
40- 58 A19 --- Bibcode Bibcode of the reference
60- 67 F8.5 d Per [0.83784/16.2547] Orbital period
69- 72 F4.1 mmag Depth [4.3/35.1] Transit depth
74- 77 F4.1 mag mag [11.8/14.6] HATSouth magnitude
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Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 I9 --- KIC [757450/11804465] Kepler Input Catalog
designation
11- 12 I2 mag mag [6/16]? Simulated magnitude
14- 15 I2 --- Ntr-8hr-1yr [4/85]? Number of transits in the simulated
light curve (8 hr per day cadence, 1 yr
light curve duration)
17- 19 I3 --- S/N-8hr-1yr [21/171]? Signal-to-noise ratio of the TCF
periodogram peak, with a 8 hr per day
cadence and 1 yr light curve duration (1)
21- 23 I3 --- Ntr-16hr-1yr [6/151]? Number of transits in the simulated
light curve (16 hr per day cadence, 1 yr
light curve duration)
25- 27 I3 --- S/N-16hr-1yr [21/506]? Signal-to-noise ratio of the TCF
periodogram peak, with a 16 hr per day
cadence and 1 yr light curve duration (1)
29- 31 I3 --- Ntr-24hr-1yr [8/218]? Number of transits in the simulated
light curve (24 hr per day cadence, 1 yr
light curve duration)
33- 35 I3 --- S/N-24hr-1yr [22/697]? Signal-to-noise ratio of the TCF
periodogram peak, with a 24 hr per day
cadence and 1 yr light curve duration (1)
37- 39 I3 --- Ntr-8hr-4yr [14/341]? Number of transits in the simulated
light curve (8 hr per day cadence, 4 yr
light curve duration)
41- 43 I3 --- S/N-8hr-4yr [21/657]? Signal-to-noise ratio of the TCF
periodogram peak, with a 8 hr per day
cadence and 4 yr light curve duration (1)
45- 47 I3 --- Ntr-16hr-4yr [27/620]? Number of transits in the simulated
light curve (16 hr per day cadence, 4 yr
light curve duration)
49- 52 I4 --- S/N-16hr-4yr [21/1798]? Signal-to-noise ratio of the TCF
periodogram peak, with a 16 hr per day
cadence and 4 yr light curve duration (1)
54- 56 I3 --- Ntr-24hr-4yr [33/890]? Number of transits in the simulated
light curve (24 hr per day cadence, 4 yr
light curve duration)
58- 61 I4 --- S/N-24hr-4yr [21/2844]? Signal-to-noise ratio of the TCF
periodogram peak, with a 24 hr per day
cadence and 4 yr light curve duration (1)
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Note (1): No value indicates entries below the threshold S/N=20.
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Byte-by-byte Description of file: table4.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 I9 --- KIC [757450/11804465] Kepler Input Catalog designation
11- 16 F6.3 d Per [1.486/41.408]? Orbital period (same as in Table 1)
18- 24 F7.3 d Per4 [51.847/143.206]? Orbital period (not in Table 1)
26- 30 F5.2 mmag Depth [5.57/36.9]? Transit depth (same as in Table 1)
32- 36 F5.2 mmag Depth4 [8.51/10.6]? Transit depth (not in Table 1)
38- 39 I2 % SR [0/94] Success rate of detecting Kepler planet
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Byte-by-byte Description of file: table6.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 A9 --- Planet Planet name (HATS-NNa)
11- 18 F8.5 d Per [0.83784/16.2547] Orbital period
20- 23 F4.1 mmag Depth [4.3/35.1] Transit depth
25- 28 F4.2 --- Fr(NA) [0.65/0.95] NA fraction (1)
30- 33 F4.1 --- S/N [0.2/74.5]? Signal-to-noise ratio of the TCF
peak (2)
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Note (1): Empty bins are treated as missing data, registered as not available
(NA) in R syntax.
Note (2): No value represents a TCF peak with power smaller than its local
median.
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History:
From electronic version of the journal
References:
Feigelson et al. Paper I. 2019AJ....158...57C 2019AJ....158...57C
Caceres et al. Paper II. 2019AJ....158...58C 2019AJ....158...58C, Cat. J/AJ/158/58
(End) Prepared by [AAS], Tiphaine Pouvreau [CDS] 20-Sep-2019