J/A+A/686/A232 AstraLux-TESS planet candidates (Lillo-Box+, 2024)
The AstraLux-TESS high-spatial resolution imaging survey.
Search for stellar companions of 215 planet candidates from TESS.
Lillo-Box J., Morales-Calderon M., Barrado D., Balsalobre-Ruza O.,
Castro-Gonzalez A., Mendigutia I., Huelamo N., Montesinos B., Vioque M.
<Astron. Astrophys. 686, A232 (2024)>
=2024A&A...686A.232L 2024A&A...686A.232L (SIMBAD/NED BibCode)
ADC_Keywords: Stars, double and multiple ; Exoplanets ; Optical
Keywords: techniques: high angular resolution - planets and satellites: general
Abstract:
Chance-aligned sources or blended companions can cause false positives
in planetary transit detections or simply bias the determination of
the candidate properties. In the era of high-precision space-based
photometers, the need for high-spatial resolution images has
demonstrated to be critical for validating and confirming transit
signals. This already applied to the Kepler mission, it is now
applicable to the TESS survey and will be critical for the PLATO
mission.
In this paper we present the results of the AstraLux-TESS survey, a
catalog of high-spatial resolution images obtained with the AstraLux
instrument at the Calar Alto observatory (Almeria, Spain) obtained in
the context of the TESS Follow-up Observing Program.
We use the lucky-imaging technique to obtain high-spatial resolution
images from planet candidate hosts included mostly in two relevant
regimes: exoplanet candidates belonging to the level-one requirement
of the TESS mission (planets with radii R<4R☉), and TESS planet
candidates around intermediate-mass main sequence stars.
Among the 185 planet host candidate stars observed, we found 13 (7%)
to be accompanied by additional sources within 2.2 arcsec separation.
Among them, six are not associated to sources in the Gaia DR3 catalog,
thus contaminating the TESS light curve. Even if no contaminants are
detected, we can provide upper limits and probabilities to the
possible existence of field contaminants through the sensitivity
limits of our images. Among the isolated hosts, we can discard
hazardous companions (bright enough to mimic a planetary transit
signals) with an accuracy below 1% for all their planets.
The results from this catalog are key for the statistical validation
of small planets (prime targets of the TESS mission) and planets
around intermediate-mass stars in the main-sequence. These two
populations of planets are hard to confirm with the radial velocity
technique because of the shallow amplitude of small planets and the
high-rotational velocities and low number of available spectral lines
in the intermediate stellar mass regime. Our results also demonstrate
the importance of this type of follow-up observations for future
transit missions like PLATO, even in the Gaia era.
Description:
High-spatial resolution imaging survey of planet candidate hosts from
the TESS space-based mission.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 119 215 Properties of observed TOIs
table2.dat 49 182 Observing setup and information
table3.dat 43 215 Results for each TOI
tablea1.dat 117 49 Detected companions in the sample of stars
observed with AstraLux presented in this work
--------------------------------------------------------------------------------
See also:
IV/39 : TESS Input Catalog version 8.2 (TIC v8.2) (Paegert+, 2021)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 I4 --- TOI TESS Object of Interest ID
6- 14 I9 --- TIC TESS Input Catalog ID
16- 22 F7.2 --- Cand Planet candidate ID, NNN.01
24- 25 A2 --- Disposition Disposition (G1)
27- 43 F17.13 deg RAdeg Right ascension (J2000) from TIC catalog
45- 61 F17.13 deg DEdeg Declination (J2000) from TIC catalog
63- 70 F8.5 mag Tmag TESS magnitude
72- 90 F19.15 d Porb ? Orbital period from TOI release
92-108 F17.14 Rgeo Rp ? Planet radius from TOI release
110-119 A10 "date" Night Night of AstraLux obs (YYMMDD)
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 I4 --- TOI TESS Object of Interest ID
6- 15 A10 "date" Night Night of AstraLux obs (YYMMDD)
17- 26 F10.4 d JD Julian date of observation (JD-2450000)
28- 31 F4.2 --- Airmass Airmass
33- 38 I6 --- Nf Number of frames in AstraLux datacube
40- 42 I3 ms TexpFrame Exposure time per frame
44- 49 F6.2 s TexpEff Effective total exposure time
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 I4 --- TOI TESS Object of Interest ID
6- 8 F3.2 --- planet Planet candidate ID
10- 13 F4.1 Rgeo Rp ?=- Planet radius
15- 16 A2 --- Disposition Disposition from TOI release (G1)
18- 21 F4.2 mag cont05 Contrast at 0.5 arcsec separation
23- 26 F4.2 mag cont1 Contrast at 1.0 arcsec separation
28- 31 F4.2 mag cont2 Contrast at 2.0 arcsec separation
33- 37 F5.3 --- BSC Blended Source Confidence probability
39- 43 F5.1 --- TPP ?=- TESS positional probability
--------------------------------------------------------------------------------
Byte-by-byte Description of file: tablea1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 A3 --- --- [TOI]
5- 8 I4 --- TOI TESS Object of Interest ID
9- 10 A2 --- n_TOI [+ ] Note on TOI (2)
12- 15 A4 --- Comp [A B Gaia] Component designation (1)
19- 24 F6.4 arcsec Sep ?=- Separation to compoment A
26- 31 F6.4 arcsec e_Sep ? Separation to compoment A error
33- 40 F8.3 deg PA []?=- Position angle to compoment A
42- 46 F5.3 deg e_PA ? Position angle to compoment A error
48- 54 F7.4 mag DmSDSSz ?=- Magnitude contrast
56- 61 F6.4 mag e_DmSDSSz ? Magnitude contrast error
63- 81 I19 --- GaiaDR3 ? Gaia DR3 counterpart
82 A1 --- n_GaiaDR3 [d] Note on GaiaDR3 (2)
84- 92 F9.4 pc d ? Distance
94-101 F8.4 pc e_d ? Distance error
103-109 F7.2 mas/yr pmRA ? Proper motion along RA
112-117 F6.2 mas/yr pmDE ? Proper motion along DE
--------------------------------------------------------------------------------
Note (1): The main target is labelled with an A, AstraLux-detected companions
are labelled with a B, and other Gaia sources are labelled Gaia.
Note (2): Notes as follows:
+ = Companions detected by AstraLux are also confidently detected with
Gaia DR3, and their proper motions and distances point to them being
physically bound to the main target
++ = The companions detected by AstraLux do not fully match the position of
a nearby Gaia DR3 source that is likely physically bound to the main
target. This can either be because the AstraLux detection corresponds
to another source or because we are detecting the binary orbital
motion of the Gaia source (see, e.g., the case of TOI-1450)
d = Gaia DR3 source ID to which the source could potentially be associated
--------------------------------------------------------------------------------
Global notes:
Note (G1): Disposition code as follows:
CP = confirmed planet
EB = eclipsing binary
PC = planet candidate
--------------------------------------------------------------------------------
History:
From Jorge Lillo-Box, jlillo(at)cab.inta-csic.es
Acknowledgements:
We thank the anonymous referee for their though revision of this
manuscript that has improved its final quality. J.L.-B. is partly
funded by grants LCF/BQ/PI20/11760023 and Ramon y Cajal fellowship
with code RYC2021-031640-I. A.C.-G., D.B., J.L.-B., M.M.-C., N.H. and
O.B.-R. are also partly funded by the Spanish
MICIU/AEI/10.13039/501100011033 grant PID2019-107061GB-C61. J.L.-B. is
also funded by the MICIU/AEI/10.13039/501100011033 and
NextGenerationEU/PRTR grant CNS2023-144309. I.M.'s research is funded
by grants PID2022-138366NA-I00, by the Spanish Ministry of Science and
Innovation/State Agency of Research MCIN/AEI/10.13039/501100011033 and
by the European Union, and by a Ramon y Cajal fellowship
RyC2019-026992-I. This work has made use of the following python
modules: astropy, (a community-developed core Python package for
Astronomy), SciPy, matplotlib (a Python library for publication
quality graphics, astroML, and numpy. This research has made use of
NASA's Astrophysics Data System (ADS) Bibliographic Services. This
research has made use of the SIMBAD database, operated at CDS. This
research has made use of the NASA Exoplanet Archive, which is operated
by the California Institute of Technology, under contract with the
National Aeronautics and Space Administration under the Exoplanet
Exploration Program. This research has made use of the Exoplanet
Follow-up Observation Program (ExoFOP; DOI: 10.26134/ExoFOP5) website,
which is operated by the California Institute of Technology, under
contract with the National Aeronautics and Space Administration under
the Exoplanet Exploration Program.
(End) Patricia Vannier [CDS] 03-Jun-2024