AuthorWang, Jason J.
Graham, James R.
De Rosa, Robert J.
Ammons, S. Mark
Bailey, Vanessa P.
Esposito, Thomas M.
Fitzgerald, Michael P.
Follette, Katherine B.
Gerard, Benjamin L.
Goodsell, Stephen J.
Greenbaum, Alexandra Z.
Larkin, James E.
Marley, Mark S.
Millar-Blanchaer, Maxwell A.
Nielsen, Eric L.
Rantakyrö, Fredrik T.
Schneider, Adam C.
Wallace, J. Kent
AffiliationUniv Arizona, Lunar & Planetary Lab
planets and satellites: dynamical evolution and stability
planets and satellites: gaseous planets
stars: individual (HR 8799)
techniques: high angular resolution
MetadataShow full item record
PublisherIOP PUBLISHING LTD
CitationJason J. Wang et al 2018 AJ 156 192
Rights© 2018. The American Astronomical Society. All rights reserved.
Collection InformationThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at email@example.com.
AbstractThe HR 8799 system uniquely harbors four young super-Jupiters whose orbits can provide insights into the system's dynamical history and constrain the masses of the planets themselves. Using the Gemini Planet Imager, we obtained down to one milliarcsecond precision on the astrometry of these planets. We assessed four-planet orbit models with different levels of constraints and found that assuming the planets are near 1:2:4:8 period commensurabilities, or are coplanar, does not worsen the fit. We added the prior that the planets must have been stable for the age of the system (40 Myr) by running orbit configurations from our posteriors through N-body simulations and varying the masses of the planets. We found that only assuming the planets are both coplanar and near 1:2:4:8 period commensurabilities produces dynamically stable orbits in large quantities. Our posterior of stable coplanar orbits tightly constrains the planets' orbits, and we discuss implications for the outermost planet b shaping the debris disk. A four-planet resonance lock is not necessary for stability up to now. However, planet pairs d and e, and c and d, are each likely locked in two-body resonances for stability if their component masses are above 6 M-Jup and 7 M-Jup, respectively. Combining the dynamical and luminosity constraints on the masses using hot-start evolutionary models and a system age of 42 +/- 5 Myr, we found the mass of planet b to be 5.8 +/- 0.5 M-Jup, and the masses of planets c, d, and e to be 7.2(-0.7)(+0.6) M-Jup each.
VersionFinal published version
SponsorsNSF [AST-1518332]; NASA [NNX15AC89G, NNX15AD95G, XRP 80NSSC18K0355]; NASA's Science Mission Directorate; Pennsylvania State University; Eberly College of Science; Pennsylvania Space Grant Consortium; U.S. Department of Energy by Lawrence Livermore National Laboratory [DE-AC52-07NA27344]; Gemini Observatory
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