J/AJ/158/100 HARPS radial velocities for HD 181433 (Horner+, 2019)
The HD 181433 planetary system: dynamics and a new orbital solution.
Horner J., Wittenmyer R.A., Wright D.J., Hinse T.C., Marshall J.P.,
Kane S.R., Clark J.T., Mengel M., Agnew M.T., Johns D.
<Astron. J., 158, 100-100 (2019)>
=2019AJ....158..100H 2019AJ....158..100H (SIMBAD/NED BibCode)
ADC_Keywords: Stars, K-type ; Radial velocities ; Exoplanets
Keywords: planetary systems - planets and satellites: general -
stars: individual: HD 181433
Abstract:
We present a detailed analysis of the orbital stability of the HD 181433
planetary system, finding it to exhibit strong dynamical instability
across a wide range of orbital eccentricities, semimajor axes, and mutual
inclinations. We also analyze the behavior of an alternative system
architecture, proposed by Campanella, and find that it offers greater
stability than the original solution, as a result of the planets being
trapped in strong mutual resonance. We take advantage of more recent
observations to perform a full refit of the system, producing a new
planetary solution. The best-fit orbit for HD 181433 d now places the
planet at a semimajor axis of 6.60±0.22 au, with an eccentricity of
0.469±0.013. Extensive simulations of this new system architecture reveal
it to be dynamically stable across a broad range of potential orbital
parameter space, increasing our confidence that the new solution represents
the ground truth of the system. Our work highlights the advantage of
performing dynamical simulations of candidate planetary systems in concert
with the orbital fitting process, as well as supporting the continuing
monitoring of radial velocity planet search targets.
Description:
Since Bouchy et al. (2009, J/A+A/496/527) published their three-planet
solution for the HD 181433 system, a large number of additional radial
velocity measurements have obtained, and the spectra are publicly available
in the European Southern Observatory (ESO) archive. Since it is well
established that radial velocity fitting processes often initially
exaggerate the eccentricity of planetary orbits (e.g., Shen & Turner
2008ApJ...685..553S 2008ApJ...685..553S; O'Toole et al. 2009MNRAS.392..641O 2009MNRAS.392..641O; Wittenmyer et al.
2013ApJS..208....2W 2013ApJS..208....2W), and that new data can often yield dramatically
different solutions for a given system, we felt that it would be prudent
to obtain a new solution for the system, based on the new data. To obtain
the longest possible time series, we obtained the publicly available High
Accuracy Radial Velocity Planet Searcher (HARPS) spectra from the ESO
archive and extracted the DRS radial velocities to perform a new analysis
on a total of 200 observational epochs.
Objects:
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RA (ICRS) DE Designation(s)
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19 25 09.57 -66 28 07.7 HD 181433 = HIP 95467
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table5.dat 23 200 HARPS radial velocities for HD 181433
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See also:
J/A+A/496/527 : Radial velocity curves of HD 47186 and HD 181433
(Bouchy+, 2009)
Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 11 F11.5 d BJD [52942.5/57971.6] Barycentric Julian Date
(BJD-2400000)
13- 18 F6.2 m/s RV [-26.51/29.4] Radial velocity
20- 23 F4.2 m/s e_RV [0.23/2.52] Uncertainty in RV
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History:
From electronic version of the journal
(End) Tiphaine Pouvreau [CDS] 10-Oct-2019