J/ApJ/838/25 Hectochelle spectroscopy for 776 Kepler stars (Guo+, 2017)
The metallicity distribution and hot Jupiter rate of the Kepler field:
Hectochelle high-resolution spectroscopy for 776 Kepler target stars.
Guo X., Johnson J.A., Mann A.W., Kraus A.L., Curtis J.L., Latham D.W.
<Astrophys. J., 838, 25-25 (2017)>
=2017ApJ...838...25G 2017ApJ...838...25G (SIMBAD/NED BibCode)
ADC_Keywords: Abundances ; Spectroscopy ; Effective temperatures ; Photometry ;
Stars, double and multiple
Keywords: catalogs; methods: statistical; planets and satellites: detection;
stars: abundances; stars: fundamental parameters;
techniques: imaging spectroscopy
Abstract:
The occurrence rate of hot Jupiters from the Kepler transit survey is
roughly half that of radial velocity surveys targeting solar
neighborhood stars. One hypothesis to explain this difference is that
the two surveys target stars with different stellar metallicity
distributions. To test this hypothesis, we measure the metallicity
distribution of the Kepler targets using the Hectochelle multi-fiber,
high-resolution spectrograph. Limiting our spectroscopic analysis to
610 dwarf stars in our sample with logg>3.5, we measure a metallicity
distribution characterized by a mean of [M/H]mean=-0.045±0.009, in
agreement with previous studies of the Kepler field target stars. In
comparison, the metallicity distribution of the California Planet
Search radial velocity sample has a mean of
[M/H]CPS,mean=-0.005±0.006, and the samples come from different
parent populations according to a Kolmogorov-Smirnov test. We refit
the exponential relation between the fraction of stars hosting a
close-in giant planet and the host star metallicity using a sample of
dwarf stars from the California Planet Search with updated
metallicities. The best-fit relation tells us that the difference in
metallicity between the two samples is insufficient to explain the
discrepant hot Jupiter occurrence rates; the metallicity difference
would need to be ∼0.2-0.3dex for perfect agreement. We also show that
(sub)giant contamination in the Kepler sample cannot reconcile the two
occurrence calculations. We conclude that other factors, such as
binary contamination and imperfect stellar properties, must also be at
play.
Description:
We measure the metallicity distribution of Kepler target stars through
a sample of 835 high-resolution spectra taken with the Hectochelle
multi-fiber spectrograph (R∼34000). Four observations pointing at four
different fields within the Kepler field were obtained (wavelength
range from 5145 to 5300Å) in 2014 Jul 15.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 53 776 Stellar parameters of 776 Kepler stars
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See also:
V/137 : Extended Hipparcos Compilation (XHIP) (Anderson+, 2012)
V/133 : Kepler Input Catalog (Kepler Mission Team, 2009)
VI/120 : High-resolution synthetic stellar library (Coelho+, 2005)
J/ApJ/348/557 : X-ray studies of stars in the Pleiades (Micela+, 1990)
J/A+A/420/183 : Spectrosc. survey in solar neighborhood (Allende Prieto+ 2004)
J/A+A/415/1153 : [Fe/H] for 98 extra-solar planet-host stars (Santos+, 2004)
J/ApJ/622/1102 : The planet-metallicity correlation. (Fischer+, 2005)
J/ApJS/159/141 : Spectroscopic properties of cool stars. I. (Valenti+, 2005)
J/ApJS/169/430 : Atmospheric param. of 1907 metal-rich stars (Robinson+, 2007)
J/A+A/487/373 : Spectroscopic parameters of 451 HARPS-GTO stars (Sousa+, 2008)
J/ApJS/190/1 : A survey of stellar families (Raghavan+, 2010)
J/A+A/535/A30 : Abundances of 12 stars in open clusters (Carrera+, 2011)
J/ApJ/742/54 : CASH project II. 14 extremely metal-poor stars (Hollek+, 2011)
J/other/Nat/486.375 : Stellar parameters of KOI stars (Buchhave+, 2012)
J/ApJ/753/90 : Stellar param. of K5 and later type Kepler stars (Mann+, 2012)
J/A+A/538/A76 : Automatic stellar spectral classification (Navarro+, 2012)
J/ApJ/771/107 : Spectroscopy of faint KOI stars (Everett+, 2013)
J/ApJ/769/57 : Equivalent widths of metal-poor stars (Frebel+, 2013)
J/ApJ/795/64 : A catalog of exoplanet physical param. (Foreman-Mackey+, 2014)
J/ApJS/211/2 : Revised properties of Q1-16 Kepler targets (Huber+, 2014)
J/ApJ/807/45 : Potentially habitable planets orbiting M dwarfs
(Dressing+, 2015)
J/AJ/150/134 : uvbyCaHβ photometry of NGC 752 (Twarog+, 2015)
J/ApJS/225/32 : Extended abundance analysis of cool stars (Brewer+, 2016)
J/ApJS/224/12 : Kepler planetary candidates. VII. 48-month (Coughlin+, 2016)
J/AJ/152/8 : Impact of stellar multiplicity on planetary systems I.
(Kraus+, 2016)
J/ApJ/822/86 : False positive proba. for Q1-Q17 DR24 KOIs (Morton+, 2016)
J/A+A/587/A64 : Physical properties of giant exoplanets (Santerne+, 2016)
http://exoplanetarchive.ipac.caltech.edu/ : NASA exoplanet archive
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 7 I7 --- KIC Kepler identifier
9- 10 I2 h RAh [19] Hour of Right Ascension (J2000)
12- 13 I2 min RAm [9/34] Minute of Right Ascension (J2000)
15- 18 F4.1 s RAs Second of Right Ascension (J2000)
20 A1 --- DE- [+] Sign of the Declination (J2000)
21- 22 I2 deg DEd [42/46] Degree of Declination (J2000)
24- 25 I2 arcmin DEm Arcminute of Declination (J2000)
27- 30 F4.1 arcsec DEs Arcsecond of Declination (J2000)
32- 35 F4.1 mag Kpmag [8.8/15] Apparent Kepler magnitude
37- 40 I4 K Teff [3980/7370] Effective temperature (1)
42- 45 F4.2 [cm/s2] log(g) [1.2/5] Log surface gravity (1)
47- 51 F5.2 [Sun] [M/H] [-2.5/0.5] Metallicity by number density (1)
53 A1 --- Bin Binary code (N=not a binary; P=Potential binary,
46 occurrences)
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Note (1): All stars have uniform empirical uncertainties on Teff of 100K,
log(g) of 0.1, and [M/H]=0.1dex. The uncertainties are estimated
in section 4 by picking out stars with multiple measurements and
comparing the best-fit parameters for each observation of the
same stars.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 26-Oct-2017