@article{f20d5856185c4615bdca52170f8c6aa9,
title = "OSSOS. IX. Two Objects in Neptune's 9:1 Resonance - Implications for Resonance Sticking in the Scattering Population",
abstract = "We discuss the detection in the Outer Solar System Origins Survey (OSSOS) of two objects in Neptune's distant 9:1 mean motion resonance at semimajor axis a ≈ 130 au. Both objects are securely resonant on 10 Myr timescales, with one securely in the 9:1 resonance's leading asymmetric libration island and the other in either the symmetric or trailing asymmetric island. These objects are the largest semimajor axis objects with secure resonant classifications, and their detection in a carefully characterized survey allows for the first robust resonance population estimate beyond 100 au. The detection of these objects implies a 9:1 resonance population of 1.1 × 104 objects with H r < 8.66 (D100 km) on similar orbits (95% confidence range of ∼(0.4-3) × 104). Integrations over 4 Gyr of an ensemble of clones spanning these objects' orbit-fit uncertainties reveal that they both have median resonance occupation timescales of ∼1 Gyr. These timescales are consistent with the hypothesis that these objects originate in the scattering population but became transiently stuck to Neptune's 9:1 resonance within the last ∼1 Gyr of solar system evolution. Based on simulations of a model of the current scattering population, we estimate the expected resonance sticking population in the 9:1 resonance to be 1000-4500 objects with H r < 8.66; this is marginally consistent with the OSSOS 9:1 population estimate. We conclude that resonance sticking is a plausible explanation for the observed 9:1 population, but we also discuss the possibility of a primordial 9:1 population, which would have interesting implications for the Kuiper Belt's dynamical history.",
author = "Kathryn Volk and Murray-Clay, {Ruth A.} and Gladman, {Brett J.} and Lawler, {Samantha M.} and Yu, {Tze Yeung Mathew} and Mike Alexandersen and Bannister, {Michele T.} and Chen, {Ying Tung} and Dawson, {Rebekah I.} and Sarah Greenstreet and Gwyn, {Stephen D.J.} and Kavelaars, {J. J.} and Lin, {Hsing Wen} and Lykawka, {Patryk Sofia} and Petit, {Jean Marc}",
note = "Funding Information: We thank the anonymous referee for helpful comments that improved this manuscript. K.V. and R.M.C. acknowledge support from NASA Solar System Workings grant NNX15AH59G. K.V. acknowledges additional support from NASA grant NNX14AG93G. S.M.L. gratefully acknowledges support from the NRC-Canada Plaskett Fellowship. M.T.B. appreciates support from UK STFC grant ST/ L000709/1. The Center for Exoplanets and Habitable Worlds is supported by the Pennsylvania State University, the Eberly College of Science, and the Pennsylvania Space Grant Consortium. Funding Information: The authors recognize and acknowledge the sacred nature of Maunakea, and appreciate the opportunity to observe from the mountain. This project could not have been a success without the dedicated staff of the Canada–France–Hawaii Telescope (CFHT). CFHT is operated by the National Research Council of Canada, the Institute National des Sciences de l{\textquoteright}Universe of the Centre National de la Recherche Scientifique of France, and the University of Hawaii, with OSSOS receiving additional access due to contributions from the Institute of Astronomy and Astrophysics, Academia Sinica, Taiwan. This work is based on observations obtained with MegaPrime/MegaCam, a joint project of CFHT and CEA/DAPNIA and on data produced and hosted at the Canadian Astronomy Data Centre and on the CANFAR VOSpace. Publisher Copyright: {\textcopyright} 2018. The American Astronomical Society. All rights reserved.",
year = "2018",
month = jun,
doi = "10.3847/1538-3881/aac268",
language = "English (US)",
volume = "155",
journal = "Astronomical Journal",
issn = "0004-6256",
publisher = "IOP Publishing Ltd.",
number = "6",
}