J/ApJS/213/5 Cool KOIs. VI. H- and K- band spectra (Muirhead+, 2014)
Characterizing the cool KOIs.
VI. H- and K-band spectra of Kepler M dwarf planet-candidate hosts.
Muirhead P.S., Becker J., Feiden G.A., Rojas-Ayala B., Vanderburg A.,
Price E.M., Thorp R., Law N.M., Riddle R., Baranec C., Hamren K.,
Schlawin E., Covey K.R., Johnson J.A., Lloyd J.P.
<Astrophys. J. Suppl. Ser., 213, 5 (2014)>
=2014ApJS..213....5M 2014ApJS..213....5M
ADC_Keywords: Stars, double and multiple ; Abundances, [Fe/H] ; Spectral types ;
Stars, masses ; Stars, distances ; Spectra, infrared ; Planets
Keywords: binaries: eclipsing; binaries: visual; planetary systems;
stars: abundances; stars: fundamental parameters;
stars: individual (KOI-2704
Abstract:
We present H- and K-band spectra for late-type Kepler Objects of
Interest (the "Cool KOIs"): low-mass stars with transiting-planet
candidates discovered by NASA's Kepler Mission that are listed on the
NASA Exoplanet Archive. We acquired spectra of 103 Cool KOIs and used
the indices and calibrations of Rojas-Ayala et al. (2012,
Cat. J/ApJ/748/93) to determine their spectral types, stellar
effective temperatures, and metallicities, significantly augmenting
previously published values. We interpolate our measured effective
temperatures and metallicities onto evolutionary isochrones to
determine stellar masses, radii, luminosities, and distances, assuming
the stars have settled onto the main sequence. As a choice of
isochrones, we use a new suite of Dartmouth predictions that reliably
include mid-to-late M dwarf stars. We identify five M4V stars: KOI-961
(confirmed as Kepler 42), KOI-2704, KOI-2842, KOI-4290, and the
secondary component to visual binary KOI-1725, which we call
KOI-1725B. We also identify a peculiar star, KOI-3497, which has Na
and Ca lines consistent with a dwarf star but CO lines consistent with
a giant. Visible-wavelength adaptive optics imaging reveals two
objects within a 1 arcsec diameter; however, the objects' colors are
peculiar. The spectra and properties presented in this paper serve as
a resource for prioritizing follow-up observations and planet
validation efforts for the Cool KOIs.
Description:
We observed the Cool KOIs with the TripleSpec Spectrograph at the
Palomar Observatory 200 inch Hale Telescope. TripleSpec is a
near-infrared slit spectrograph covering 1.0 to 2.5um simultaneously
with a resolving power (λ/Δλ) of 2700.
Observations were carried out in 2011 June and August for the KOIs
from Borucki et al. (2011, Cat. J/ApJ/736/19), with results published
in a previous letter (Muirhead et al. 2012, Cat. J/ApJ/750/L37). In
July and August of 2012, we augmented observations to include all of
the Cool KOIs selected in Batalha et al. (2013, Cat. J/ApJS/204/24).
In 2013 July and August, we observed the remaining Cool KOIs listed on
the NASA Exoplanet Archive (NEA) as of the observations.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 114 106 Cool KOI stellar properties
fits.dat 145 2 Summary of FITS files in subdirectory fits
fits/* . 2 H- and K-band spectra FITS files
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See also:
I/322 : UCAC4 Catalogue (Zacharias+, 2012)
VII/233 : The 2MASS Extended sources (IPAC/UMass, 2003-2006)
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
J/ApJS/210/20 : Small Kepler planets radial velocities (Marcy+, 2014)
J/ApJS/207/35 : Kepler pipeline signal-to-noise studies (Christiansen+, 2013)
J/ApJS/204/24 : Kepler planetary candidates. III. (Batalha+, 2013)
J/AJ/145/52 : Abundances of late K & M dwarfs in binary systems (Mann+, 2013)
J/other/Nat/486.375 : Stellar parameters of KOI stars (Buchhave+, 2012)
J/ApJS/199/30 : Effective temperature scale for KIC stars (Pinsonneault+, 2012)
J/ApJ/757/112 : Stellar diameters. II. K and M-stars (Boyajian+, 2012)
J/ApJ/753/90 : Stellar param. of K5 and later type Kepler stars (Mann+, 2012)
J/ApJ/750/L37 : Stellar parameters of low-mass KOIs (Muirhead+, 2012)
J/ApJ/748/93 : K-band spectra for 133 nearby M dwarfs (Rojas-Ayala+, 2012)
J/ApJS/197/8 : Kepler's cand. multiple transiting planets (Lissauer+, 2011)
J/ApJ/738/170 : False positive Kepler planet candidates (Morton+, 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/other/A+ARV/18.67 : Accurate masses and radii of normal stars (Torres+, 2010)
J/ApJS/159/141 : Spectroscopic properties of cool stars. I. (Valenti+, 2005)
J/A+AS/141/371 : Low-mass stars evolutionary tracks+isochrones (Girardi+, 2000)
J/A+A/337/403 : Low-mass stars evolutionary models (Baraffe+ 1998)
J/A+A/327/1039 : Structure and evolution of low-mass stars (Chabrier+ 1997)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 I4 --- KOI [1/4875] KOI Number
6- 7 A2 --- m_KOI KOI multiplicity (A or B for visual binaries)
9- 16 I8 --- KIC KIC identifier
18- 21 I4 K Teff [3187/4342]? Stellar effective temperature (1)
23- 26 I4 K E_Teff ? Positive uncertainty in Teff (1)
28- 31 I4 K e_Teff ? Negative uncertainty in Teff (1)
33- 37 F5.2 [Sun] Fe/H [-0.5/0.5]? Iron abundance using Rojas-Ayala et
al. (R12; Cat. J/ApJ/748/93) calibration (1)
39- 42 F4.2 [Sun] e_Fe/H ? Uncertainty in Fe/H (1)
44- 48 F5.2 [Sun] M/H ? Overall metallicity using Rojas-Ayala et
al. (R12; Cat. J/ApJ/748/93) calibration (1)
50- 53 F4.2 [Sun] e_M/H ? Uncertainty in M/H (1)
55- 57 A3 --- SpT KHM spectral type using Rojas-Ayala et
al. 2012 (R12; J/ApJ/748/93) calibration (1)
59- 62 F4.2 Msun M* [0.1/0.8]? Stellar mass (2)
64- 67 F4.2 Msun e_M* ? Uncertainty in M* (2)
69- 72 F4.2 Rsun R* [0.1/0.7]? Stellar radius (2)
74- 77 F4.2 Rsun e_R* ? Uncertainty in R* (2)
79- 81 I3 pc Dist [20/622]? Estimated distance to star (3)
83- 87 F5.2 [Sun] Fe/H-T ? Iron abundance using Terrien et al.
(T12; 2012ApJ...747L..38T 2012ApJ...747L..38T) calibration (4)
89- 92 F4.2 [Sun] e_Fe/H-T ? Uncertainty in Fe/H-T (4)
94- 98 F5.2 [Sun] Fe/H-M ? Iron abundance using Mann et al.
(M13; Cat. J/AJ/145/52) calibration (4)
100-103 F4.2 [Sun] e_Fe/H-M ? Uncertainty in Fe/H-M (4)
105-109 F5.2 [Sun] M/H-M ? Overall metallicity using Mann et al.
(M13; Cat. J/AJ/145/52) calibration (4)
111-114 F4.2 [Sun] e_M/H-M ? Uncertainty in M/H-M (4)
--------------------------------------------------------------------------------
Note (1): Stellar parameters determined with:
* the K-band spectroscopic indices of Rojas-Ayala et al. 2012 (J/ApJ/748/93),
referred to as R12 in the table. Metallicity measurements for stars earlier
than M0 (effective temperature >4000K) represent an extrapolation of the
calibrations.
* KHM refers to the Kirkpatrick et al. (1991ApJS...77..417K 1991ApJS...77..417K) spectral type
system.
* For KOI 961, we use the effective temperature from Muirhead et al. 2012
(J/ApJ/750/L37), which was determined by comparison to empirical
measurements of Barnard's Star.
Note (2): Stellar parameters determined by interpolation onto a 5-Gyr isochrone
from the Dartmouth Stellar Evolution Database (Dotter et al.
2008ApJS..178...89D 2008ApJS..178...89D).
Note (3): Distance determined by combining the predicted Mk from the Dartmouth
isochrones to the apparent K-band magnitude from 2MASS
Cutri et al. (2003, Cat. II/246).
Note (4): For completeness, we include metallicity determinations using H-band
indices of Terrien et al. (2012ApJ...747L..38T 2012ApJ...747L..38T), referred to as T12,
and the K-band indices of Mann et al. (2013, Cat. J/AJ/145/52),
referred to as M13.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: fits.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 5 I5 --- Nx Number of pixels along X-axis
7- 9 I3 --- Ny Number of pixels along Y-axis (Targets)
11- 14 I4 Kibyte Size Size of the file
16- 24 A9 --- FileName Name of the FITS file in subdirectory fits
26-145 A120 --- Title Title of the file
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History:
From electronic version of the journal
References:
Muirhead et al. Paper I. 2012ApJ...750L..37M 2012ApJ...750L..37M Cat. J/ApJ/750/L37
Johnson et al. Paper II: KOI-254. 2012AJ....143..111J 2012AJ....143..111J
Muirhead et al. Paper III: KOI 961. 2012ApJ...747..144M 2012ApJ...747..144M
Swift et al. Paper IV: Kepler-32. 2013ApJ...764..105S 2013ApJ...764..105S
Muirhead et al. Paper V: KOI-256. 2013ApJ...767..111M 2013ApJ...767..111M
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 01-Sep-2014