J/ApJ/753/90 Stellar parameters of K5 and later type Kepler stars (Mann+, 2012)
They might be giants: luminosity class, planet occurrence, and
planet-metallicity relation of the coolest Kepler target stars.
Mann A.W., Gaidos E., Lepine S., Hilton E.J.
<Astrophys. J., 753, 90 (2012)>
=2012ApJ...753...90M 2012ApJ...753...90M
ADC_Keywords: Effective temperatures ; Stars, double and multiple ;
Stars, late-type ; Planets
Keywords: planetary systems; planets and satellites: detection;
stars: abundances; stars: fundamental parameters; stars: late-type
Abstract:
We estimate the stellar parameters of late K- and early M-type Kepler
target stars. We obtain medium-resolution visible spectra of 382 stars
with KP-J>2 (≃K5 and later spectral type). We determine luminosity
class by comparing the strength of gravity-sensitive indices (CaH,
K I, Ca II, and Na I) to their strength in a sample of stars of known
luminosity class. We find that giants constitute 96%±1% of the
bright (KP<14) Kepler target stars, and 7%±3% of dim (KP>14)
stars, significantly higher than fractions based on the stellar
parameters quoted in the Kepler Input Catalog (KIC). The KIC effective
temperatures are systematically (110+15-35K) higher than
temperatures we determine from fitting our spectra to PHOENIX stellar
models. Through Monte Carlo simulations of the Kepler exoplanet
candidate population, we find a planet occurrence of 0.36±0.08 when
giant stars are properly removed, somewhat higher than when a KIC log
g>4 criterion is used (0.27±0.05). Last, we show that there is no
significant difference in g-r color (a probe of metallicity) between
late-type Kepler stars with transiting Earth-to-Neptune-size exoplanet
candidates and dwarf stars with no detected transits. We show that a
previous claimed offset between these two populations is most likely
an artifact of including a large number of misidentified giants.
Description:
Observations were obtained between 2011 June 16 and August 28 with the
SuperNova Integral Field Spectrograph (SNIFS) at the University of
Hawaii 2.2m telescope on Mauna Kea and the Boller and Chivens CCD
Spectrograph (CCDS) or the Mark III spectrograph (MkIII) at the MDM
Observatory 1.3m McGraw-Hill telescope on Kitt Peak. SNIFS is an
optical integral field spectrograph with R∼1300 that splits the signal
with a dichroic mirror into blue (3000-5200Å) and red
(5000-9500Å) channels. The CCDS and MkIII spectrographs cover
5700-9300Å and 4400-8300Å with R∼1150 and ∼2300, respectively.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 46 382 Parameters of observed Kepler targets
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See also:
V/133 : Kepler Input Catalog (Kepler Mission Team, 2009)
J/ApJS/210/1 : KIC asteroseismic data (Chaplin+, 2014)
J/ApJS/204/24 : Kepler planetary candidates. III. (Batalha+, 2013)
J/A+A/557/A70 : Evolved planet hosts - stellar parameters (Mortier+, 2013)
J/A+A/551/A112 : Metallicity-giant planet correlation (Mortier+, 2013)
J/ApJS/199/30 : Eff. temperature scale for KIC stars (Pinsonneault+, 2012)
J/ApJ/752/72 : KIC metallicity correlation (Dodson-Robinson, 2012)
J/ApJ/750/L37 : Stellar parameters of low-mass KOIs (Muirhead+, 2012)
J/ApJ/749/152 : Asteroseismic analysis of 22 solar-type stars (Mathur+, 2012)
J/ApJ/746/36 : RV standard deviation in the M2K survey (Gaidos+, 2012)
J/ApJ/738/170 : False positive Kepler planet candidates (Morton+, 2011)
J/ApJ/736/L25 : Habitability of Kepler planetary cand. (Kaltenegger+, 2011)
J/ApJ/736/19 : Kepler planetary candidates. II. (Borucki+, 2011)
J/ApJ/728/117 : Kepler planetary candidates. I. (Borucki+, 2011)
J/AJ/142/112 : KIC photometric calibration (Brown+, 2011)
J/A+A/514/A97 : Late-type stars HR spectra (Lopez-Santiago+ 2010)
J/other/Sci/330.653 : Detected planets in the Eta-Earth Survey (Howard+, 2010)
J/A+A/487/373 : Spectroscopic parameters of 451 HARPS-GTO stars (Sousa+, 2008)
J/ApJ/622/1102 : The planet-metallicity correlation. (Fischer+, 2005)
J/A+A/415/1153 : [Fe/H] for 98 extra-solar planet-host stars (Santos+, 2004)
J/A+AS/105/311 : M giants spectra and photometry (Fluks+, 1994)
http://keplergo.arc.nasa.gov/ : Kepler Science Center home page
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 8 I8 --- KIC KIC identifier (Cat. V/133)
10 A1 --- f_KIC [d] no atmospheric parameters (1)
12- 15 F4.1 mag Kpmag [6/16] Kepler magnitude
17- 19 F3.1 [cm/s2] log(g) [0/5]? KIC log of the surface gravity
21- 24 I4 K Te(K) [3203/5051]? KIC effective temperature
26- 30 A5 --- Inst Instrument (2)
32- 36 A5 --- LCl Luminosity classification (Dwarf or Giant)
38- 41 I4 K Teff [3000/5000] Our effective temperature
43- 46 I4 K e_Teff [20/140] The 1σ error in Teffs
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Note (1):
d = No temperatures or log(g) values present in the KIC.
Note (2):
SNIFS = SuperNova Integral Field Spectrograph (University of Hawaii
2.2-meter telescope);
CCDS = Boller & Chivens CCD Spectrograph (MDM Observatory 1.3m
McGraw-Hill Telescope);
MkIII = Mark III spectrograph (MDM Observatory 1.3m McGraw-Hill Telescope).
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 14-Feb-2014