J/MNRAS/501/5309 Confirming known planetary trends with Kepler (Hansen+, 2021)
Confirming known planetary trends using a photometrically selected Kepler
sample.
Hansen J.T., Casagrande L., Ireland M.J., Lin J.
<Mon. Not. R. Astron. Soc., 501, 5309-5318 (2021)>
=2021MNRAS.501.5309H 2021MNRAS.501.5309H (SIMBAD/NED BibCode)
ADC_Keywords: Exoplanets ; Stars, double and multiple ; Effective temperatures ;
Abundances, [Fe/H] ; Stars, masses ; Stars, diameters ; Optical
Keywords: catalogues - planets and satellites: fundamental parameters -
stars: fundamental parameters - stars: planetary systems
Abstract:
Statistical studies of exoplanets and the properties of their host
stars have been critical to informing models of planet formation.
Numerous trends have arisen in particular from the rich Kepler data
set, including that exoplanets are more likely to be found around
stars with a high metallicity and the presence of a 'gap' in the
distribution of planetary radii at 1.9R⊕. Here we present a
new analysis on the Kepler field, using the APOGEE spectroscopic
survey to build a metallicity calibration based on Gaia, 2MASS and
Stromgren photometry. This calibration, along with masses and radii
derived from a Bayesian isochrone fitting algorithm, is used to test a
number of these trends with unbiased, photometrically derived
parameters, albeit with a smaller sample size in comparison to recent
studies. We recover that planets are more frequently found around
higher metallicity stars; over the entire sample, planetary
frequencies are 0.88±0.12 per cent for [Fe/H]<0 and 1.37±0.16 per
cent for [Fe/H]≥0 but at two sigma we find that the size of
exoplanets influences the strength of this trend. We also recover the
planet radius gap, along with a slight positive correlation with
stellar mass. We conclude that this method shows promise to derive
robust statistics of exoplanets. We also remark that spectrophotometry
from Gaia DR3 will have an effective resolution similar to narrow band
filters and allow to overcome the small sample size inherent in this
study.
Description:
We have compiled a photometric catalogue of stars in the Kepler field
utilizing photometry from Gaia, Stromgren, and 2MASS catalogues. We
created a metallicity calibration based on APOGEE spectroscopy to
obtain a metallicity for our photometric sample, and then performed
well-defined colour and magnitude cuts to ensure our data set was a
representative sample of the underlying population of stars. We then
derived temperatures and angular diameters using the IFRM, which were
then used to derive stellar radii and stellar mass through Bayesian
isochrone fitting. The resultant parameters were compared favourably
with previous results from the literature, especially giving stellar
radii with relative uncertainties around 3.4 per cent. Planetary radii
uncertainties of 6.2 per cent hence indicate a major uncertainty
contribution from the Kepler planet to star ratio.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
koiparam.dat 131 312 Stellar and planetary parameters for the final
list of KOIs remaining after the selection
procedure described in the text
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See also:
V/133 : Kepler Input Catalog (Kepler Mission Team, 2009)
J/ApJ/736/19 : Kepler planetary candidates. II. (Borucki+, 2011)
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
Byte-by-byte Description of file: koiparam.dat
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Bytes Format Units Label Explanations
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1- 8 I8 --- KIC KIC identifier
10- 18 A9 --- KOI KOI identifier (K0NNNN.NN)
20- 28 A9 --- Status KOI disposition (CONFIRMED or CANDIDATE)
30- 40 F11.6 K Teff Effective temperature
42- 53 F12.9 [-] [Fe/H] Fe/H abundance ratio
55- 65 F11.9 Msun M* Star mass
67- 77 F11.9 Msun e_M* Error on M*
79- 89 F11.9 Rsun R* Star radius
91-101 F11.9 Rsun e_R* Error on R*
103-116 F14.9 Rgeo Rp Planet radius
118-131 F14.9 Rgeo e_Rp Error on Rp
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History:
From electronic version of the journal
(End) Ana Fiallos [CDS] 23-Oct-2023