J/MNRAS/490/3806 Exoplanets & variable stars in 47 Tuc field (Nardiello+, 2019)
A PSF-based Approach to TESS High quality data Of Stellar clusters (PATHOS).
I. Search for exoplanets and variable stars in the field of 47 Tuc.
Nardiello D., Borsato L., Piotto G., Colombo L.S., Manthopoulou E.E.,
Bedin L.R., Granata V., Lacedelli G., Libralato M., Malavolta L.,
Montalto M., Nascimbeni V.
<Mon. Not. R. Astron. Soc., 490, 3806-3823 (2019)>
=2019MNRAS.490.3806N 2019MNRAS.490.3806N (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, globular ; Stars, variable ; Photometry ; Optical
Keywords: techniques: image processing - techniques: photometric -
stars: variables: general - globular clusters: individual: NGC 104
Abstract:
The TESS mission will survey ∼85 per cent of the sky, giving us
the opportunity of extracting high-precision light curves of millions
of stars, including stellar cluster members. In this work, we present
our project 'A PSF-based Approach to TESS High quality data Of
Stellar clusters' (PATHOS), aimed at searching and characterize
candidate exoplanets and variable stars in stellar clusters using our
innovative method for the extraction of high-precision light curves of
stars located in crowded environments. Our technique of light-curve
extraction involves the use of empirical point spread functions
(PSFs), an input catalogue and neighbour-subtraction. The PSF-based
approach allows us to minimize the dilution effects in crowded
environments and to extract high-precision photometry for stars in the
faint regime (G>13). For this pilot project, we extracted,
corrected, and analysed the light curves of 16641 stars located in a
dense region centred on the globular cluster 47 Tuc. We were able to
reach the TESS magnitude T∼16.5 with a photometric precision of
∼1 per cent on the 6.5-h time-scale; in the bright regime we were able
to detect transits with depth of ∼34 parts per million. We searched
for variables and candidate transiting exoplanets. Our pipeline
detected one planetary candidate orbiting a main-sequence star in the
Galactic field. We analysed the period-luminosity distribution for
red-giant stars of 47 Tuc and the eclipsing binaries in the field.
Light curves are uploaded on the Mikulski Archive for Space Telescopes
under the project PATHOS.
Description:
For this pilot work, we used FFIs collected in Sector-1. FFIs are
obtained on board by co-adding series of 2s exposures into a 30min
exposure time image. Observations have been carried out by TESS
between 2018 July 25 and 2018 August 22 and cover ∼27.83d, during
which 1282 usable FFIs were generated. The target of this work,
47 Tuc, is located on the CCD 2 of Camera 3.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table2.dat 110 34 List of eclipsing binaries
table3.dat 83 54 List of the analysed RGB stars in 47 Tuc
table4.dat 83 24 List of the analysed AGB stars in 47 Tuc
--------------------------------------------------------------------------------
See also:
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
IV/38 : TESS Input Catalog - v8.0 (TIC-8) (Stassun+, 2019)
J/MNRAS/495/4924 : Exoplanets in Southern open cluster (Nardiello+, 2020)
J/MNRAS/498/5972 : Variables & dippers in young associations (Nardiello, 2020)
https://archive.stsci.edu/hlsp/pathos : PATHOS Home Page
Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 I2 --- EB EB sequential number
4- 14 F11.9 deg RAdeg Gaia DR2 Right ascension (ICRS) at Ep=2015.5
16- 27 F12.8 deg DEdeg Gaia DR2 Declination (ICRS) at Ep=2015.5
29- 47 I19 --- GaiaDR2 Gaia DR2 Source ID
49- 53 F5.2 mag Tmag TESS T magnitude
55- 59 F5.2 mag Gmag Gaia DR2 G magnitude
61- 65 F5.2 mag BPmag Gaia DR2 G_BP magnitude
67- 71 F5.2 mag RPmag Gaia DR2 G_RP magnitude
73- 79 F7.3 mas/yr pmRA Proper motion along RA from Gaia DR2,
pmRA*cosDE
81- 87 F7.3 mas/yr pmDE Proper motion along Dec from Gaia DR2
89- 96 F8.6 d Per Period
98-106 A9 --- Note Notes
108-110 A3 --- Ref References (1)
--------------------------------------------------------------------------------
Note (1): References as follows:
1 = Clement et al. (2001AJ....122.2587C 2001AJ....122.2587C, updated to 2017), Cat. V/150
2 = Pawlak et al. (2016AcA....66..421P 2016AcA....66..421P), Cat. J/AcA/66/421
3 = Samus et al. (2017ARep...61...80S 2017ARep...61...80S), Cat. B/gcvs
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table3.dat table4.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 A3 --- Type [RGB AGB] Type
5- 15 F11.9 deg RAdeg Gaia DR2 Right ascension (ICRS) at Ep=2015.5
16- 27 F12.8 deg DEdeg Gaia DR2 Declination (ICRS) at Ep=2015.5
29- 47 I19 --- GaiaDR2 Gaia DR2 Source ID
49- 53 F5.2 mag Tmag TESS T magnitude
55- 59 F5.2 mag Gmag Gaia DR2 G magnitude
61- 65 F5.2 mag BPmag Gaia DR2 G_BP magnitude
67- 72 F6.3 mag RPmag Gaia DR2 G_RP magnitude
74- 78 F5.2 d Per Period
80- 83 F4.2 d e_Per ? Period error
--------------------------------------------------------------------------------
History:
From electronic version of the journal
References:
Nardiello et al., Paper II 2020MNRAS.495.4924N 2020MNRAS.495.4924N, Cat. J/MNRAS/495/4924
Nardiello et al., Paper III 2020MNRAS.498.5972N 2020MNRAS.498.5972N, Cat. J/MNRAS/498/5972
(End) Patricia Vannier [CDS] 26-Oct-2020