J/AJ/158/197 Radial velocities & light curves of KELT-24 (Rodriguez+, 2019)
KELT-24b: a 5MJ planet on a 5.6 day well-aligned orbit around the young V=8.3
F-star HD 93148.
Rodriguez J.E., Eastman J.D., Zhou G., Quinn S.N., Beatty T.G., Penev K.,
Johnson M.C., Cargile P.A., Latham D.W., Bieryla A., Collins K.A.,
Dressing C.D., Ciardi D.R., Relles H.M., Murawski G., Nishiumi T.,
Yonehara A., Ishimaru R., Yoshida F., Gregorio J., Lund M.B., Stevens D.J.,
Stassun K.G., Gaudi B.S., Colon K.D., Pepper J., Narita N., Awiphan S.,
Chuanraksasat P., Benni P., Zambelli R., Garrison L.H., Wilson M.L.,
Cornachione M.A., Wang S.X., Labadie-Bartz J., Rodriguez R., Siverd R.J.,
Yao X., Bayliss D., Berlind P., Calkins M.L., Christiansen J.L.,
Cohen D.H., Conti D.M., Curtis I.A., Depoy D.L., Esquerdo G.A., Evans P.,
Feliz D., Fulton B.J., Holoien T.W.-S., James D.J., Jayasinghe T.,
Jang-Condell H., Jensen E.L.N., Johnson J.A., Joner M.D., Khakpash S.,
Kielkopf J.F., Kuhn R.B., Manner M., Marshall J.L., McLeod K.K.,
McCrady N., Oberst T.E., Oelkers R.J., Penny M.T., Reed P.A., Sliski D.H.,
Shappee B.J., Stephens D.C., Stockdale C., Tan T.-G., Trueblood M.,
Trueblood P., Villanueva S., Wittenmyer R.A., Wright J.T.
<Astron. J., 158, 197-197 (2019)>
=2019AJ....158..197R 2019AJ....158..197R (SIMBAD/NED BibCode)
ADC_Keywords: Stars, bright ; Stars, F-type ; Radial velocities ; Photometry ;
Exoplanets
Keywords: Transit photometry - Exoplanet astronomy -
Exoplanet detection methods - Radial velocity
Abstract:
We present the discovery of KELT-24 b, a massive hot Jupiter orbiting
a bright (V=8.3 mag, K=7.2 mag) young F-star with a period of 5.6 days.
The host star, KELT-24 (HD 93148), has a Teff=6509-49+50 K, a mass
of M*=1.460-0.059+0.055 M☉, a radius of
R*=1.506±0.022 R☉, and an age of 0.78-0.42+0.61 Gyr. Its
planetary companion (KELT-24 b) has a radius of RP=1.272±0.021 RJ
and a mass of MP=5.18-0.22+0.21 MJ, and from Doppler tomographic
observations, we find that the planet's orbit is well-aligned to its host
star's projected spin axis (λ=2.6-3.6+5.1). The young age
estimated for KELT-24 suggests that it only recently started to evolve
from the zero-age main sequence. KELT-24 is the brightest star known
to host a transiting giant planet with a period between 5 and 10 days.
Although the circularization timescale is much longer than the age of
the system, we do not detect a large eccentricity or significant
misalignment that is expected from dynamical migration. The brightness
of its host star and its moderate surface gravity make KELT-24b an
intriguing target for detailed atmospheric characterization through
spectroscopic emission measurements since it would bridge the current
literature results that have primarily focused on lower mass hot Jupiters
and a few brown dwarfs.
Description:
The Kilodegree Extremely Little Telescope (KELT) survey
(http://keltsurvey.org) uses two 42 mm telescopes to discover hot Jupiters
orbiting bright host stars (7<V<12), planets well-suited for detailed
atmospheric characterization (Pepper et al. 2007PASP..119..923P 2007PASP..119..923P,
2012PASP..124..230P 2012PASP..124..230P, 2018haex.bookE.128P 2018haex.bookE.128P). With one telescope in Sonita,
AZ, and the other at the South African Astronomical Observatory (SAAO)
in Sutherland, South Africa, KELT surveys over 85% of the entire sky with
a 20-30 minute cadence. The planetary companion orbiting HD 93148
(hereafter KELT-24 b) was identified from a joint analysis of five separate
KELT-North fields that cover the celestial northern polar cap, KN25 through
KN29 (although KELT-24 was only observed in two of the five fields).
The multiband photometric follow-up of KELT-24 b was obtained from the
KELT Follow-Up Network (KELT-FUN, Collins et al. 2018, J/AJ/156/234).
KELT-FUN is a worldwide network of amateur astronomers, small-college
observatories, and observing time on the Las Cumbres Observatory
telescope network (Brown et al. 2013PASP..125.1031B 2013PASP..125.1031B).
To confirm the planetary nature of KELT-24 b, 59 spectra were obtained
using the Tillinghast Reflector Echelle Spectrograph (TRES; Furesz 2008,
PhD thesis Univ. Szeged) on the 1.5 m Tillinghast Reflector located at
the Fred L. Whipple Observatory (FLWO) on Mt. Hopkins, AZ. TRES has a
resolving power of R∼44000, and has been highly successful in confirming
exoplanet candidates from both ground- and space-based transit surveys.
We reduced the TRES spectra and extracted RVs following the procedure
described in Buchhave et al. (2010, J/ApJ/720/1118) and Quinn et al.
(2012, J/ApJ/756/L33) with the exception of the creation of the template
spectrum used.
Objects:
-----------------------------------------------------------
RA (ICRS) DE Designation(s) (Period)
-----------------------------------------------------------
10 47 38.35 +71 39 21.2 HD 93148 = KELT-24 (P=5.55)
-----------------------------------------------------------
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
fig1.dat 38 960 The KELT discovery light curve of KELT-24
fig2.dat 41 1983 The KELT-FUN light curves of KELT-24 b
table3.dat 38 19 Relative out of transit radial velocities
for KELT-24 from TRES
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See also:
J/ApJ/720/1118 : i-band photometry of HAT-P-16 (Buchhave+, 2010)
J/ApJ/756/L33 : Radial velocities of 2 hot Jupiters in Praesepe (Quinn+, 2012)
J/AJ/156/234 : KELT transit false positive catalog for TESS (Collins+, 2018)
Byte-by-byte Description of file: fig1.dat
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Bytes Format Units Label Explanations
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1- 16 F16.8 d JD Julian Date; Terrestrial Time (TT)
18- 27 F10.8 --- NFlux [0.974322/1.01895] Normalized flux
29- 38 F10.8 --- e_NFlux [0.0013549/0.00558809] Uncertainty in NFlux
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Byte-by-byte Description of file: fig2.dat
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Bytes Format Units Label Explanations
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1 I1 --- Obs [1/9] Observation code (1)
3- 16 F14.6 d BJD Barycentric Julian Date; TDB
18- 25 F8.6 --- NFlux [0.973309/2.95666] Normalized flux
27- 34 F8.6 --- e_NFlux [0.000309/0.007222] Uncertainty in NFlux
36- 41 F6.4 --- Air [1.0482/2.0964]? Airmass
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Note (1): Observation code as follows:
1 = Sloan i band from KeplerCam on 2019-03-30;
2 = Sloan z band from ULMT on 2019-03-30;
3 = Sloan i band from KeplerCam on 2019-04-10;
4 = Sloan z band from ULMT on 2019-04-11;
5 = R band from SOTES on 2019-04-16;
6 = Sloan i band from CROW on 2019-04-27;
7 = Sloan z band from LCO TFN on 2019-04-27;
8 = Sloan z band from KAO on 2019-05-03;
9 = Sloan z band from KAP on 2019-05-03.
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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- 14 F14.6 d BJD Barycentric Julian Date; TDB
16- 20 F5.1 m/s RV [-29.5/914.2] Radial velocity
22- 25 F4.1 m/s e_RV [20.4/58.1] Uncertainty in RV
27- 32 F6.1 m/s Bis [-199.2/197.2] Bisector span
34- 38 F5.1 m/s e_Bis [42.4/116] Uncertainty in Bis
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History:
From electronic version of the journal
(End) Prepared by [AAS], Tiphaine Pouvreau [CDS] 16-Jan-2020