J/MNRAS/496/1197 Young exoplanets in TESS sectors 1-5 (Battley+, 2020)
A search for young exoplanets in Sectors 1-5 of the TESS full-frame images.
Battley M.P., Pollacco D., Armstrong D.J.
<Mon. Not. R. Astron. Soc., 496, 1197-1216 (2020)>
=2020MNRAS.496.1197B 2020MNRAS.496.1197B (SIMBAD/NED BibCode)
ADC_Keywords: Associations, stellar ; Exoplanets ; Positional data ; Optical ;
Infrared
Keywords: techniques: photometric - planets and satellites: detection -
planets and satellites: general - stars: rotation -
open clusters and associations: general
Abstract:
Young (<1Gyr) exoplanets represent a critically important area of
exoplanet research, as they offer the opportunity to learn about the
formation and early dynamic history of exoplanetary systems. However,
finding young exoplanets is significantly complicated by the fast
rotation and complex activity of their young host stars, which are
often not well handled by state-of-the-art automatic pipelines. This
work presents an alternative LOWESS-based pipeline focused
specifically on detrending young stellar light curves from the 30-min
cadence full-frame images produced by the Transiting Exoplanet Survey
Satellite (TESS), and includes improvements such as automatic peak
cutting of stellar variability and interpolation over masked transits
to improve periodogram visibility and returned transit shapes. This
work presents the details of the developed pipeline, along with
initial results from its application to young stars within stellar
associations in Sectors 1-5 of the TESS data. While no new exoplanet
candidate signals were found in this work, interesting results
included the recovery of all known 2-min TOIs around young stars in
Sectors 1-5 from 30-min data alone, the recovery of the young
exoplanet DS Tuc Ab, a number of young eclipsing binaries and a wide
array of interesting rotation. A sensitivity analysis was also
undertaken for each star, showing how the recovery of injected planets
varied with both depth and period for each individual target.
Challenges for future searches for young exoplanets are discussed, the
largest being stellar rotation with periods less than 1d and a lack of
a large sample of confirmed young stars.
Description:
Combining Gagne et al.'s (2018ApJ...856...23G 2018ApJ...856...23G, Cat. J/ApJ/856/23)
initial census of bona-fide/high-probability stellar association
members with new high-probability members added in the two following
BANYAN Σ papers (Gagne & Faherty 2018ApJ...862..138G 2018ApJ...862..138G, Cat.
J/ApJ/862/138; Gagne et al. 2018ApJ...860...43G 2018ApJ...860...43G, Cat. J/ApJ/860/43)
yielded a total of 2977 objects spread over the 27 nearest known young
stellar associations. Gagne, Faherty & Mamajek (2018ApJ...865..136G 2018ApJ...865..136G)
later expanded the BANYAN Σ tool to also include the two new
Argus (Zuckerman 2019ApJ...870...27Z 2019ApJ...870...27Z) and Volans-Carina associations
using the same membership criteria, so these were also added to the
initial target list, to give a final sample of 3076 young stars in
stellar associations.
The various BANYAN survey results were combined into a single tabular
target list using the TOPCAT table handling software (Taylor
2005ASPC..347...29T 2005ASPC..347...29T). This list was then cross-matched with version 8
of the TESS input catalogue (TIC) (Stassun et al. 2019AJ....158..138S 2019AJ....158..138S,
Cat. IV/38) using a 3arcsec radius. For this work, only the sources
viewed in Sectors 1-5 were considered.
Given the increased availability and comparatively clean light curves
provided by the DIA pipeline of Oelkers and Stassun (Oelkers & Stassun
2019RNAAS...3....8O 2019RNAAS...3....8O, 2018AJ....156..132O 2018AJ....156..132O), this pipeline was chosen to
extract light curves from the TESS FFIs in this work, resulting in
light curves for 256 individual objects.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
stars.dat 51 256 List of studied stars
table4.dat 218 19840 Full sensitivity analysis table for each of the
256 stars with DIA light-curves
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See also:
IV/39 : TESS Input Catalog version 8.2 (TIC v8.2) (Paegert+, 2021)
Byte-by-byte Description of file: stars.dat
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Bytes Format Units Label Explanations
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1- 23 A23 --- Name Source name
25- 37 F13.9 deg RAdeg Right ascension (J2000)
39- 51 F13.9 deg DEdeg Declination (J2000)
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 23 A23 --- Name Source name
25- 37 F13.9 deg RAdeg Right ascension (J2000)
39- 51 F13.9 deg DEdeg Declination (J2000)
53 I1 --- Sector [1/5] TESS sector
55- 56 I2 d Pinj Injected period
58- 62 F5.3 --- Rp/R* Planet radius to star radius ratio
64- 75 F12.9 --- Sep Orbital separation (in R* units) (1)
77- 88 F12.9 d Prot Rotation period
90- 107 F18.13 d Epochmax Epoch of maximum
109- 120 F12.9 d Pmax Maximum period
122- 133 F12.9 d P2max Second highest period
135- 146 F12.9 d P3max Third highest period
148- 158 E11.9 [-] loglike Logarithm of the maximum likelihood
160- 164 A5 --- Recov [TRUE /FALSE] Indicates if the injected
signal is recovered (2)
166- 212 A47 --- Notes Remarks
214- 218 A5 --- Assoc Association
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Note (1): The orbital separation was derived from Kepler's Third Law. If the
information on a star's mass or radius was not available, the
corresponding planet was assigned an orbital separation of 17R*,
representing the average orbital separation for planets with 8-d
periods (in the middle of the period range) on the NASA Exoplanet
Archive.
Note (2): Injected signals were considered to have been 'recovered' if they
appeared as one of the three highest peaks in the BLS periodogram,
ignoring harmonics of the maximum peak.
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History:
From electronic version of the journal
(End) Ana Fiallos [CDS] 29-Jun-2023