J/AJ/167/74 Correspondence TOIs & TESS control stars (Littlefield+, 2024)
High-resolution Imaging of a TESS Control Sample: Verifying a Deficit of Close-
in Stellar Companions to Exoplanet Host Stars.
Littlefield C., Howell S.B., Ciardi D.R., Lester K.V., Everett M.E.,
Furlan E., Matson R.A., Fajardo-Acosta S.B., Gnilka C.L.
<Astron. J., 167, 74 (2024)>
=2024AJ....167...74L 2024AJ....167...74L
ADC_Keywords: Exoplanets; Interferometry; Positional data
Keywords: Speckle interferometry ; Exoplanet astronomy
Abstract:
The large number of exoplanets discovered with the Transiting
Exoplanet Survey Satellite (TESS) means that any observational biases
from TESS could influence the derived stellar multiplicity statistics
of exoplanet host stars. To investigate this problem, we obtained
speckle interferometry of 207 control stars whose properties in the
TESS Input Catalog (TIC) closely match those of an exoplanetary host
star in the TESS Object of Interest (TOI) catalog, with the objective
of measuring the fraction of these stars that have companions within
∼1.2". Our main result is the identification of a bias in the creation
of the control sample that prevents the selection of binaries with
0.1"≲ρ≲1.2" and Δmag≲3. This bias is the result of large
astrometric residuals that cause binaries with these parameters to
fail the quality checks used to create the TIC, which in turn causes
them to have incomplete stellar parameters (and uncertainties) in the
TIC. Any stellar multiplicity study that relies exclusively upon TIC
stellar parameters to identify its targets will struggle to select
unresolved binaries in this parameter space. Left uncorrected, this
selection bias disproportionately excludes high-mass-ratio binaries,
causing the mass-ratio distribution of the companions to deviate
significantly from the uniform distribution expected of FGK-type field
binaries. After accounting for this bias, the companion rate of the
FGK control stars is consistent with the canonical 46%±2% rate
from Raghavan et al., and the mass-ratio distribution agrees with that
of binary TOI host stars. There is marginal evidence that the
control-star companions have smaller projected orbital separations
than TOI host stars from previous studies.
Description:
Our observations were carried out with the 'Alopeke and Zorro speckle
cameras on the 8m Gemini North and Gemini South telescopes,
respectively. Some of our observations were obtained using the 3.5m
WIYN telescope and the NN-EXPLORE Exoplanet Stellar Speckle Imager
(NESSI) instrument, which is conceptually similar to (and served as
the prototype for) both 'Alopeke and Zorro. The NESSI observations
used the same filters (562nm and 832nm) as the Gemini observations,
but the resolution is worse by a factor of ∼2 because of the smaller
aperture.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 47 26 Properties of detected companions to control stars
table2.dat 95 207 Correspondence between TOIs and control stars
--------------------------------------------------------------------------------
See also:
IV/38 : TESS Input Catalog - v8.0 (TIC-8) (Stassun+, 2019)
J/ApJS/190/1 : A survey of stellar families (Raghavan+, 2010)
J/AJ/141/45 : Speckle observations of HIP stars (Horch+, 2011)
J/AJ/142/19 : Speckle observations of KOI (Howell+, 2011)
J/ApJ/745/19 : Binary systems in Taurus-Auriga (Kraus+, 2012)
J/ApJS/208/9 : Intrinsic colors and temperatures of PMS stars (Pecaut+, 2013)
J/AJ/152/8 : Impact of star multipl on planetary systems I. (Kraus+, 2016)
J/AJ/153/117 : KOIs companions from high-resolution imaging (Hirsch+, 2017)
J/AJ/156/102 : TESS Input Catalog and Candidate Target List (Stassun+, 2018)
J/AJ/157/211 : Unresolved binarie in TESS with speckle imaging (Matson+, 2019)
J/AJ/157/216 : Star multiplicity rate of Mdwarfs within 25 pc (Winters+, 2019)
J/AJ/159/19 : SOAR TESS survey. I. (Ziegler+, 2020)
J/ApJS/254/39 : Exoplanet candidates from TESS first 2yr obs (Guerrero+, 2021)
J/AJ/161/134 : Survey of stellar & planetary comp. within 25pc (Hirsch+, 2021)
J/AJ/161/164 : Observation of 186 TESS stars with NESSI (WYIN) (Howell+, 2021)
J/AJ/162/75 : Speckle obs TESS exoplanet host stars. II. (Lester+, 2021)
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 I9 --- TIC TESS Input Catalog identifier
11- 15 F5.3 arcsec rho-832nm [0.02/2.11] Separation, arcseconds at 832nm
17- 20 F4.2 mag dmag-832nm [0.02/10] Magnitude difference at 832nm
22- 28 F7.3 deg theta-832nm [18.9/359] Position Angle, E of N, at 832nm
30- 34 F5.3 arcsec rho-562nm [0.04/2.09]? Separation, arcseconds at 562nm
36- 39 F4.2 mag dmag-562nm [0.27/4.77]? Magnitude difference at 562nm
41- 47 F7.3 deg theta-562nm [18.4/355]? Position Angle, E of N, at 562nm
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 I9 --- TIC TESS Input Catalog identifier, control star
11- 14 I4 --- TOI TESS Object of Interest identifier
16- 16 A1 --- Code B=Control star Binary (Table 1)
18- 25 F8.3 pc Dist-c [17.1/1371] Distance, control
27- 32 F6.3 pc e_Dist-c [0.01/80] Uncertainty in Dist-c
34- 41 F8.3 pc Dist-t [17/1387] Distance, TOI
43- 48 F6.3 pc e_Dist-t [0/56] Uncertainty in Dist-t
50- 55 F6.4 Rsun Radius-c [0.31/4.78] Radius, control
57- 62 F6.4 Rsun e_Radius-c [0.009/0.4] Uncertainty in Radius-c
64- 69 F6.4 Rsun Radius-t [0.32/4.02] Radius, TOI
71- 76 F6.4 Rsun e_Radius-t [0/0.3] Uncertainty in Radius-t
78- 81 I4 K Teff-c [3240/9510] Effective temperature, control
83- 85 I3 K e_Teff-c [98/590] Uncertainty in Teff-c
87- 90 I4 K Teff-t [3220/9620] Effective temperature, TOI
92- 95 I4 K e_Teff-t [0/6000] Uncertainty in Teff-t
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) Prepared by [AAS], Coralie Fix [CDS], 29-Apr-2024