J/ApJS/222/14 Planetary candidates from 1st yr K2 mission (Vanderburg+, 2016)
Planetary candidates from the first year of the K2 mission.
Vanderburg A., Latham D.W., Buchhave L.A., Bieryla A., Berlind P.,
Calkins M.L., Esquerdo G.A., Welsh S., Johnson J.A.
<Astrophys. J. Suppl. Ser., 222, 14 (2016)>
=2016ApJS..222...14V 2016ApJS..222...14V (SIMBAD/NED BibCode)
ADC_Keywords: Stars, double and multiple ; Planets ; Stars, diameters ;
Radial velocities ; Abundances
Keywords: methods: data analysis; planets and satellites: detection;
techniques: photometric
Abstract:
The Kepler Space Telescope is currently searching for planets
transiting stars along the ecliptic plane as part of its extended K2
mission. We processed the publicly released data from the first year
of K2 observations (Campaigns 0, 1, 2, and 3) and searched for
periodic eclipse signals consistent with planetary transits. Out of
the 59174 targets that we searched, we detect 234 planetary candidates
around 208 stars. These candidates range in size from gas giants to
smaller than the Earth, and range in orbital periods from hours to
over a month. We conducted initial reconnaissance spectroscopy of 68
of the brighter candidate host stars, and present high-resolution
optical spectra for these stars. We make all of our data products,
including light curves, spectra, and vetting diagnostics available to
users online.
Description:
During Campaign 0, K2 observed a field centered at
RAJ2000=06:33:11.14,DEJ2000=+21:35:16.40, for a period of 80 days
between March and May of 2014.
During Campaign 1, K2 observed a field centered at
RAJ2000=11:35:45.51,DEJ2000=+01:25:02.28 for 83 days between June and
August of 2014.
Field 2 of the K2 mission is centered at
RAJ2000=16:24:30.34,DEJ2000=-22:26:50.28, and was observed for 79 days
between 2014 August and November.
Field 3 of the K2 mission is centered at
RAJ2000=22:26:39.68,DEJ2000=-11:05:47.99, and was observed for 69 days
between 2014 November and 2015 February.
We observed 68 stars with the high-resolution Tillinghast Reflector
Echelle Spectrograph (TRES; on the 1.5m telescope at Fred L. Whipple
Observatory (FLWO) on Mt. Hopkins, Arizona; R=44000) at least once,
collecting a total of 101 spectra, and extracted the spectra using the
procedure described in Buchhave et al. (2010, J/ApJ/720/1118). See
tables 3 and 4.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 117 234 Planet candidate parameters
table2.dat 75 208 Stellar parameters for planet candidate host stars
table3.dat 75 68 Summary of spectroscopic observations with TRES
table4.dat 84 101 List of individual observations with TRES
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See also:
V/133 : Kepler Input Catalog (Kepler Mission Team, 2009)
J/MNRAS/456/2260 : K2 Variability Catalogue II (Armstrong+, 2016)
J/A+A/582/A33 : K2-19b light curve (Armstrong+, 2015)
J/A+A/579/A19 : K2 Variable Catalogue (Armstrong+, 2015)
J/ApJ/810/95 : Kepler pipeline S/N studies. II. 2011 (Christiansen+, 2015)
J/AJ/150/85 : Photometry and spectroscopy of HAT-P-56 (Huang+, 2015)
J/A+A/579/A19 : K2 Variable Catalogue (Armstrong+, 2015)
J/ApJS/217/31 : Kepler planetary candidates. VI. 4yr Q1-Q16 (Mullally+, 2015)
J/ApJ/800/135 : HARPS-N radial velocities of KOI-69 (Dressing+, 2015)
J/ApJ/800/85 : Teff, radii and luminosities of cool dwarfs (Newton+, 2015)
J/ApJ/784/45 : Kepler's multiple planet candidates. III. (Rowe+, 2014)
J/ApJS/210/20 : Small Kepler planets radial velocities (Marcy+, 2014)
J/A+A/559/A36 : Exoplanets WASP-65b and WASP-75b (Gomez Maqueo Chew+, 2013)
J/ApJS/208/9 : Intrinsic colors and temperatures of PMS stars (Pecaut+, 2013)
J/ApJS/207/35 : Kepler pipeline signal-to-noise studies (Christiansen+, 2013)
J/MNRAS/426/739 : Velocities for 7 transiting hot Jupiters (Hellier+, 2012)
J/ApJ/757/112 : Stellar diameters. II. K and M-stars (Boyajian+, 2012)
J/other/Nat/486.375 : Stellar parameters of KOI stars (Buchhave+, 2012)
J/ApJS/199/24 : The first three quarters of Kepler mission (Tenenbaum+, 2012)
J/AJ/142/112 : KIC photometric calibration (Brown+, 2011)
J/ApJ/738/170 : False positive Kepler planet candidates (Morton+, 2011)
J/ApJ/736/19 : Kepler planetary candidates. II. (Borucki+, 2011)
J/ApJ/720/1118 : i-band photometry of HAT-P-16 (Buchhave+, 2010)
http://cfop.ipac.caltech.edu/k2/ : ExoFOP-K2 home page
http://archive.stsci.edu/prepds/k2sff/ : K2 extracted lightcurves "K2SFF"
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1 I1 --- Type [0/1] Transit type (0=regular or 1=deep transit)
3- 14 F12.2 --- ID [201126503.01/206543223.01] Identifier
16- 17 I2 h RAh Hour of Right Ascension (J2000)
19- 20 I2 min RAm Minute of Right Ascension (J2000)
22- 27 F6.3 s RAs Second of Right Ascension (J2000)
29 A1 --- DE- Sign of the Declination (J2000)
30- 31 I2 deg DEd Degree of Declination (J2000)
33- 34 I2 arcmin DEm Arcminute of Declination (J2000)
36- 40 F5.2 arcsec DEs Arcsecond of Declination (J2000)
42- 46 F5.2 mag Kpmag [8.2/18.2] Kepler magnitude
48- 58 F11.8 d Per [0.18/55] Period
60- 67 F8.3 d T0 [1939.1/2165.8] Barycentric Julian Date of
transit time; BJD-2454833
69- 73 F5.2 h T1-4 [0.3/18.8] Transit duration between 1st and
4th contacts
75- 78 F4.2 --- Depth [0/1] Transit impact parameter
80- 86 F7.4 % e_Depth [0.01/39] Percent uncertainty in Depth
88- 94 F7.5 --- Rp/R* [0.01/0.64] Planet to stellar radii ratio
96-100 F5.2 Rsun R* [0.1/17.3] Stellar radius
102-108 F7.3 Rgeo Rpfit [0.7/233] Estimated planetary radius (1)
111-117 F7.3 Rgeo Rpdel [0.7/217] Estimated planetary radius (2)
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Note (1): Calculated by multiplying the best-fit Ratio by R*.
Note (2): Calculated by multiplying sqrtδ with R*. Our best-fit
parameters can sometimes converge to unphysical high impact
parameter values, in which case Rpdel is a more reliable estimator
of the planetary radius.
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 9 I9 --- EPIC [201126503/206543223] EPIC identifier
11- 15 F5.2 mag Kpmag [8.2/18.2] Kepler magnitude
17- 18 I2 h RAh Hour of Right Ascension (J2000)
20- 21 I2 min RAm Minute of Right Ascension (J2000)
23- 28 F6.3 s RAs Second of Right Ascension (J2000)
30 A1 --- DE- Sign of the Declination (J2000)
31- 32 I2 deg DEd Degree of Declination (J2000)
34- 35 I2 arcmin DEm Arcminute of Declination (J2000)
37- 41 F5.2 arcsec DEs Arcsecond of Declination (J2000)
43 I1 --- Camp [0/3] Campaign number
(see the "Description" section above)
45- 49 I5 K Teff [2586/46696] Stellar effective temperature (1)
51 A1 --- f_Teff [a-g] Flag on Teff (2)
53- 57 F5.2 Rsun R* [0.1/17.3] Stellar radius based on Teff
59- 63 F5.1 mas/yr pm [0/319.5]? Total proper motion of host star
65- 69 F5.2 --- Rpm [-4/10.5]? Reduced proper motion
(HJ=5+J+5log10pm)
71- 73 A3 --- Giant [Yes] Possible giant? (3)
75 I1 --- NTRES [1/5]? Number of TRES spectroscopic observations
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Note (1): Our photometric estimate of the stellar effective temperature,
obtained following the procedure outlined in Section 5.1.
Note (2): Flag as follows:
a = Teff derived using the Boyajian et al. (2013ApJ...771...40B 2013ApJ...771...40B)
V-K relation.
b = Teff derived using the Boyajian et al. (2013ApJ...771...40B 2013ApJ...771...40B)
B-V relation.
c = Teff derived using the Boyajian et al. (2013ApJ...771...40B 2013ApJ...771...40B)
g-r relation.
d = Teff derived using the Gonzalez Hernandez & Bonifacio (2009,
J/A+A/497/497) J-K relation.
e = Teff derived by interpolating the Mamajek H-K spectral type tables.
f = Teff derived by interpolating the Mamajek V-R spectral type tables.
g = Teff derived using the Casagrande et al. (2008, J/MNRAS/389/585)
V-K relation.
Note (3): A binary flag noting possible giant host stars based on
reduced proper motion.
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 9 I9 --- EPIC [201295312/206535016] EPIC identifier
11 I1 --- NTRES [1/5] Number of TRES spectroscopic observations
13- 16 I4 K Teff [4382/6022]? SPC effective temperature output
18- 19 I2 K e_Teff [50/60]? Uncertainty in Teff
21- 24 F4.2 [cm/s2] log(g) [4.2/4.8]? SPC Log surface gravity output
26- 29 F4.2 [cm/s2] e_log(g) [0.1/0.2]? Uncertainty in log(g)
31- 35 F5.2 [-] [M/H] [-0.4/0.5]? SPC metallicity output
37- 40 F4.2 [-] e_[M/H] [0.08]? Uncertainty in [M/H]
42 A1 --- l_vsini Limit flag on vsini
44- 47 F4.1 km/s vsini [2.5/14.5]? SPC equatorial rotational velocity
output
49- 51 F3.1 km/s e_vsini [0.5]? Uncertainty in vsini
53- 58 F6.2 m/s RVel [-38.9/43.6]? Absolute radial velocity
60- 63 F4.2 m/s e_RVel [0.1/0.6]? Uncertainty in RVel
65- 68 I4 m/s stdev [1/2174]? Observed scatter in radial velocity
70- 71 I2 m/s sigma [14/87]? Typical measurement uncertainty
73- 75 A3 --- Notes [,a-g] Additional notes (1)
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Note (1): Note as follows:
a = One exposure is significantly weaker than others, so multi-order
velocity results are not reported.
b = Composite spectrum, so SPC and multi-order velocity results are
not reported.
c = Moonlight contamination, so interpret results with caution. SPC and
multi-order velocities may not be reported depending on the
contamination.
d = Cool star with Teff<4200, so SPC results are not reported.
e = Weak CCF with the normalized cross correlation peak height <0.9,
so SPC results are not reported.
f = Weak exposure with S/N per resolution element less than 25,
so SPC results are not reported
g = Surface gravity log(g)<4.2, so SPC results are not reported.
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 9 I9 --- EPIC [201295312/206535016] EPIC identifier
11- 23 F13.5 d BJD Barycentric Julian Date; UTC
25- 30 F6.2 km/s ARVel [-75.8/95.8] Absolute radial velocity (1)
32- 38 F7.1 km/s RRVel [-4302/329]? Relative radial velocity (2)
40- 43 F4.1 km/s e_RRVel [14/96]? Uncertainty in RRV
45- 46 I2 km/s vsini [0/20] Equatorial rotational velocity (3)
48- 52 F5.1 --- SNRe [7/113] Signal-to-Noise (4)
54- 57 I4 s Exp [250/4500] Exposure time
59- 84 A26 --- Notes Additional note
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Note (1): Absolute RV is measured from the cross correlation of the TRES order
containing the Mg b triplet near 519nm, as described in Section 5.2.
The accuracy of these measurements is perhaps 100m/s, mostly limited
by systematic errors in establishing the transfer to the IAU Radial
Velocity Standard Stars.
Note (2): Relative RV is measured from the multi-order velocity analysis
described in Section 5.2, and can have a precision as good as about
15m/s.
Note (3): Of the model spectrum producing the highest cross-correlation peak,
and is only a rough estimate of vsini. The values should not be
trusted for rotational velocities slower than about 5km/s.
Note (4): Per resolution element in the continuum near 519nm.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 08-Feb-2016