J/AJ/158/227 Asteroseismic parameters of RGB stars (Grunblatt+, 2019)
Giant planet occurrence within 0.2 au of low-luminosity red giant branch stars
with K2.
Grunblatt S.K., Huber D., Gaidos E., Hon M., Zinn J.C., Stello D.
<Astron. J., 158, 227 (2019)>
=2019AJ....158..227G 2019AJ....158..227G (SIMBAD/NED BibCode)
ADC_Keywords: Stars, giant ; Asteroseismology ; Stars, diameters ;
Stars, masses ; Effective temperatures ; Abundances, [Fe/H] ;
Magnitudes ; Stars, distances ; Exoplanets
Keywords: planetary systems - planet-star interactions -
planets and satellites: detection -
planets and satellites: dynamical evolution and stability -
stars: fundamental parameters - stars: oscillations
Abstract:
Every Sun-like star will eventually evolve into a red giant, a transition
which can profoundly affect the evolution of a surrounding planetary
system. The timescale of dynamical planet evolution and orbital decay
has important implications for planetary habitability, as well as
post-main-sequence star and planet interaction, evolution, and internal
structure. Here, we investigate these effects by estimating planet
occurrence around 2476 low-luminosity red giant branch (LLRGB) stars
observed by the NASA K2 mission. We measure stellar masses and radii using
asteroseismology, with median random uncertainties of 3.7% in mass and
2.2% in radius. We compare this planet population to the known population
of planets around dwarf Sun-like stars, accounting for detection efficiency
differences between the stellar populations. We find that 0.49%±0.28%
of LLRGB stars host planets larger than Jupiter with orbital periods less
than 10 days, tentatively higher than main-sequence stars hosting similar
planets (0.15%±0.06%). Our results suggest that the effects of stellar
evolution on the occurrence of close-in planets larger than Jupiter
are not significant until stars have begun ascending substantially up
the red giant branch (≳5-6 R☉).
Description:
Over 10000 stars observed by the K2 mission (Howell et al. 2014,
Cat. IV/34) were investigated to estimate planet occurrence around
low-luminosity red giant branch (LLRGB) stars. Searching for planet
transits around these moderately evolved stars captures the intrinsic
photometric variability due to the oscillations of these stars as
well. These oscillations can be used to measure stellar densities and
surface gravities through asteroseismology, which as used to calculate
planet occurrence statistics with more precision than current
spectroscopic techniques would allow (Huber et al. 2013,
J/ApJ/767/127; Petigura et al. 2017, J/AJ/154/107). The sample was
restrictied to 2476 of these stars whose radii are large enough for
precise characterization with asteroseismology but are also small
enough to allow planet transit detection using the 30 minute cadence
data of K2.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 192 2476 Asteroseismic parameters
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See also:
IV/34 : K2 Ecliptic Plane Input Catalog (EPIC) (Huber+, 2017)
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
J/ApJ/767/127 : Asteroseismic solutions for 77 Kepler stars (Huber+, 2013)
J/ApJS/224/2 : K2 EPIC stellar properties for 138600 targets (Huber+, 2016)
J/AJ/154/107 : California-Kepler Survey (CKS). I. 1305 stars (Petigura+, 2017)
J/ApJS/236/42 : Asteroseismology of ∼16000 Kepler red giants (Yu+, 2018)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 9 I9 --- EPIC [201089316/248295571] K2 Ecliptic Plane
Input Catalog identifier
11- 20 F10.6 uHz numax [50.14016/295.136787] Best-fit frequency
of maximum power νmax
22- 30 F9.6 uHz e_numax [0/10.74829] Uncertainty in numax
32- 40 F9.6 uHz Dnu [5.88815/20.95513] Regular frequency spacing
Δν
42- 49 F8.6 uHz e_Dnu [0.0121/0.5534] Uncertainty in Dnu
51- 59 F9.6 ppm Amp [0/59.1365] Maximum oscillation amplitude
61- 70 F10.6 --- S/B [-41.02358/13.99596] Asteroseismic
signal-to-background ratio
72- 79 F8.6 Rsun Rad-AS [3.287173/7.997912] Asteroseismic radius
81- 88 F8.6 Rsun e_Rad-AS [0.066606/0.368089] Uncertainty in Rad-AS
90- 97 F8.6 Msun Mass-AS [0.521351/2.474164] Asteroseismic mass
99-106 F8.6 Msun e_Mass-AS [0.023016/0.160355] Uncertainty in Mass-AS
108-118 F11.6 K Teff-iso [3686.339893/5667.750393] Effective
temperature from isoclassify
120-129 F10.6 Rsun Rad-iso [2.361485/154.402496] Radius from
isoclassify
131-134 I4 K Teff-EPIC [3908/6222] EPIC (Cat. IV/34) recorded
effective temperature
143-147 F5.3 [cm/s2] logg [1.567/4.971] EPIC recorded surface gravity
152-157 F6.3 [-] [Fe/H] [-2.232/0.21] EPIC recorded metallicity
162-170 F9.6 mag GPMag [-4.903268/3.861973] Gaia DR2 (Cat. I/345)
absolute GP magnitude
172-179 F8.6 mag BP-RP [0.988816/2.326923] Gaia DR2 BP-RP color
181-192 F12.6 pc Dist [89.791594/40816.326531] Gaia DR2 distance
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History:
From electronic version of the journal
(End) Prepared by [AAS], Tiphaine Pouvreau [CDS] 23-Jan-2020