OSSOS finds an exponential cutoff in the size distribution of the cold classical Kuiper Belt
| Autor: | Michele T. Bannister, Stephen Gwyn, Ying-Tung Chen, Volk Kathryn, Jean-Marc Petit, Mike Alexandersen, J. J. Kavelaars, Brett Gladman |
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| Přispěvatelé: | Univers, Transport, Interfaces, Nanostructures, Atmosphère et environnement, Molécules (UMR 6213) (UTINAM), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC), Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS) |
| Jazyk: | angličtina |
| Rok vydání: | 2021 |
| Předmět: |
Solar System
Planetesimal [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP] Population 0211 other engineering and technologies FOS: Physical sciences 02 engineering and technology Astrophysics classical Kuiper belt objects Protoplanetary disk 01 natural sciences Kuiper belt 0103 physical sciences trans-Neptunian objects Trans-Neptunian object education 010303 astronomy & astrophysics Minor planet 021101 geological & geomatics engineering Physics Earth and Planetary Astrophysics (astro-ph.EP) education.field_of_study Astronomy and Astrophysics Accretion (astrophysics) 13. Climate action Space and Planetary Science Streaming instability Astrophysics::Earth and Planetary Astrophysics Astrophysics - Earth and Planetary Astrophysics |
| Zdroj: | The Astrophysical journal letters The Astrophysical journal letters, Bristol : IOP Publishing, 2021, 920 (2), pp.L28. ⟨10.3847/2041-8213/ac2c72⟩ |
| ISSN: | 2041-8205 2041-8213 |
| DOI: | 10.3847/2041-8213/ac2c72 |
| Popis: | The cold main classical Kuiper Belt consists of those non-resonant small solar system bodies with low orbital inclinations and orbital semi-major axes between 42.4 and 47.7 au. These objects likely formed \textit{in situ} and the population has experienced minimal collisional modification since formation. Using the Outer Solar System Origins Survey (OSSOS) ensemble sample and characterization, combined with constraints from deeper surveys and supported by evidence from the Minor Planet Center catalog and the Deep Ecliptic Survey, we determine the absolute magnitude $H_r$ distribution of the cold classical belt from $H_r\simeq5$ to 12 (roughly diameters of 400 km to 20 km). We conclude that the cold population's $H_r$ distribution exhibits an exponential cutoff at large sizes. Exponential cutoffs at large sizes are not a natural outcome of pair-wise particle accretion but exponentially tapered power-law size distributions are a feature of numerical simulations of planetesimal formation via a streaming instability. Our observation of an exponential cutoff agrees with previous observational inferences that no large objects ($D \gtrsim 400$ km) exist in the cold population. We note that the asymptotic slope of the $H_r$ distribution is consistent with $\alpha \sim 0.4$ and this asymptotic slope is also found in streaming instability modelling of planetesimal formation and is thus not necessarily associated with achieving collisional equilibrium. Studies of the transneptunian region are providing the parameters that will enable future streaming-instability studies to determine the initial conditions of planetesimal formation in the $\approx$45 au region of the Sun's protoplanetary disk. Comment: 20 pages, 2 figures, accepted in AAS Journals |
| Databáze: | OpenAIRE |
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