J/AJ/163/281 Radial velocity, transit & occultation of WASP-4 (Turner+, 2022)
Characterizing the WASP-4 System with TESS and Radial Velocity Data;
Constraints on the Cause of the Hot Jupiter's Changing Orbit and Evidence of an
Outer Planet.
Turner J.D., Flagg L., Ridden-Harper A., Jayawardhana R.
<Astron. J., 163, 281 (2022)>
=2022AJ....163..281T 2022AJ....163..281T
ADC_Keywords: Exoplanets; Stars, high-velocity; Spectra, optical;
Radial velocities; Occultations
Keywords: Star-planet interactions ; Exoplanet dynamics ; Extrasolar
gaseous giant planets ; Exoplanets ; Radial velocity ; Timing
variation methods ; Transit photometry
Abstract:
Orbital dynamics provide valuable insights into the evolution and
diversity of exoplanetary systems. Currently, only one hot Jupiter,
WASP-12b, is confirmed to have a decaying orbit. Another, WASP-4b,
exhibits hints of a changing orbital period that could be caused by
orbital decay, apsidal precession, or the acceleration of the system
toward the Earth. We have analyzed all data sectors from NASA's
Transiting Exoplanet Survey Satellite together with all radial
velocity (RV) and transit data in the literature to characterize
WASP-4b's orbit. Our analysis shows that the full RV data set is
consistent with no acceleration toward the Earth. Instead, we find
evidence of a possible additional planet in the WASP-4 system, with an
orbital period of ∼7000days and Mcsin(i) of
5.47-0.43+0.44MJup. Additionally, we find that the transit
timing variations of all of the WASP-4b transits cannot be explained
by the second planet but can be explained with either a decaying orbit
or apsidal precession, with a slight preference for orbital decay.
Assuming the decay model is correct, we find an updated period of
1.338231587±0.000000022days, a decay rate of -7.33±0.71ms/yr,
and an orbital decay timescale of τ=P/|P.|=15.77±1.57Myr. If
the observed decay results from tidal dissipation, we derive a
modified tidal quality factor of Q*'=5.1±0.9x104, which is an
order of magnitude lower than values derived for other hot Jupiter
systems. However, more observations are needed to determine
conclusively the cause of WASP-4b's changing orbit and to confirm the
existence of an outer companion.
Description:
Transiting Exoplanet Survey Satellite (TESS) observed WASP-4b in
Sector 2 (2018 August 22 - 2018 September 20), Sector 28 (2020 July 30
- 2020 August 26), and Sector 29 (2020 August 26 - 2020 September 22).
We combined all available Radial velocity data of WASP-4 in the
literature in our analysis.
Objects:
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RA (2000) DE Designation(s) (Period)
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23 34 15.09 -42 03 41.0 WASP-4 = WASP-4 (P=1.338231587d)
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 48 142 All WASP-4b radial velocity measurements
table5.dat 46 183 All WASP-4b transit and occultation times
refs.dat 78 22 References used in this paper
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See also:
J/AJ/137/3826 : Two transits of the giant planet WASP-4b (Winn+, 2009)
J/A+A/524/A25 : Radial Velocities on 6 exoplanet host stars (Triaud+, 2010)
J/A+A/530/A5 : WASP-4b Ks-band detection of thermal emission (Caceres+, 2011)
J/MNRAS/414/1278 : Eccentricities of transiting planets (Pont+, 2011)
J/ApJ/733/127 : Four transits of WASP-4b (Sanchis-Ojeda+, 2011)
J/A+A/539/A159 : WASP-4b transit griz light curves (Nikolov+, 2012)
J/MNRAS/421/2342 : 4 Kepler systems transit time observations (Steffen+, 2012)
J/ApJS/208/16 : Kepler transit timing observations. VIII. (Mazeh+, 2013)
J/ApJ/785/126 : HIRES radial velocity measurements (Knutson+, 2014)
J/A+A/588/L6 : WASP-12 transit light curves (Maciejewski+ 2016)
J/A+A/602/A107 : 231 transiting planets eccentricity and mass (Bonomo+, 2017)
J/A+A/600/A30 : Limb-darkening for TESS satellite (Claret, 2017)
J/AJ/154/4 : Times of transits and occultations of WASP-12b (Patra+, 2017)
J/AcA/68/371 : WASP and KELT planet transits (Maciejewski+, 2018)
J/AJ/157/217 : Transit times of 5 hot Jupiter WASP exoplanets (Bouma+, 2019)
J/AJ/158/190 : Main sequence hot Jupiter hosts with astrometry (Hamer+, 2019)
J/AJ/158/243 : A search for multiplanet systems with TESS (Pearson, 2019)
J/MNRAS/490/4230 : Transiting planet WASP-4b (Southworth+, 2019)
J/ApJ/893/L29 : WASP-4 RVs & hot Jupiter predict period changes (Bouma+, 2020)
J/AJ/159/150 : Transit times of 11 hot Jupiters (Patra+, 2020)
J/ApJ/888/L5 : Transits, occultation times and RVs of WASP-12b (Yee+, 2020)
J/AJ/161/72 : 180 Transit and occultation times for WASP-12b (Turner+, 2021)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 14 F14.6 d BJD [2454359/2458724] Barycentric Julian date; TDB
16- 26 F11.5 m/s RVel [-299/58017] Radial velocity per instrument
28- 35 F8.5 m/s e_RVel [1.7/60] Uncertainty in RVel
37- 43 A7 --- Inst Instrument name; CORALIE, HARPS or HIRES
45- 48 A4 --- Ref Reference used for RVel
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 3 A3 --- Type Event type (1)
5- 19 F15.7 d BJD [2454368/2459112] Barycentric Julian date; TDB
21- 28 F8.6 d e_BJD [5e-05/0.003] The 1σ uncertainty in Time
30- 34 I5 --- Epoch [-1073/2471] Epoch number
36- 40 A5 --- TimeRef Reference used for time
42- 46 A5 --- TransRef Reference used fot transit
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Note (1): Types as follows:
tra = Transit (179 occurrences)
occ = Occultation (4 occurrences)
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Byte-by-byte Description of file: refs.dat
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Bytes Format Units Label Explanations
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1- 5 A5 --- Ref Reference code
7- 26 A20 --- Author Main autor of the reference
28- 46 A19 --- BIB BIBcode
48- 63 A16 --- Cat. Catalog in Vizier
65- 78 A14 --- Note Note or comment
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History:
From electronic version of the journal
(End) Prepared by [AAS], Coralie Fix [CDS], 03-Oct-2022