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Title: Dynamical Evolution of the Debris Disk after a Satellite Catastrophic Disruption around Saturn

Abstract

The hypothesis of the recent origin of Saturn’s rings and its midsized moons is actively debated. It was suggested that a proto-Rhea and a proto-Dione might have collided recently, giving birth to the modern system of midsized moons. It has also been suggested that the rapid viscous spreading of the debris may have implanted mass inside Saturn’s Roche limit, giving birth to its modern ring system. However, this scenario has only been investigated in a very simplified way for the moment. This paper investigates it in detail to assess its plausibility by using N -body simulations and analytical arguments. When the debris disk is dominated by its largest remnant, N -body simulations show that the system quickly reaccretes into a single satellite without significant spreading. On the other hand, if the disk is composed of small particles, analytical arguments suggest that the disk experiences dynamical evolutions in three steps. The disk starts significantly excited after the impact and collisional damping dominates over the viscous spreading. After the system flattens, the system can become gravitationally unstable when particles are smaller than ∼100 m. However, the particles grow faster than spreading. Then, the system becomes gravitationally stable again and accretion continues at a slower pace, but spreadingmore » is inhibited. Therefore, the debris is expected to reaccrete into several large bodies. In conclusion, our results show that such a scenario may not form today’s ring system. In contrast, our results suggest that today’s midsized moons are likely reaccreted from such a catastrophic event.« less

Authors:
 [1];  [2]
  1. Earth-Life Science Institute/Tokyo Institute of Technology, 2-12-1 Tokyo (Japan)
  2. Institut de Physique du Globe, 75005 Paris (France)
Publication Date:
OSTI Identifier:
22663436
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astronomical Journal (Online); Journal Volume: 154; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; COMPUTERIZED SIMULATION; DAMPING; EVOLUTION; MASS; MOON; ORIGIN; PARTICLES; RINGS; SATURN PLANET; STABILITY

Citation Formats

Hyodo, Ryuki, and Charnoz, Sébastien. Dynamical Evolution of the Debris Disk after a Satellite Catastrophic Disruption around Saturn. United States: N. p., 2017. Web. doi:10.3847/1538-3881/AA74C9.
Hyodo, Ryuki, & Charnoz, Sébastien. Dynamical Evolution of the Debris Disk after a Satellite Catastrophic Disruption around Saturn. United States. doi:10.3847/1538-3881/AA74C9.
Hyodo, Ryuki, and Charnoz, Sébastien. Sat . "Dynamical Evolution of the Debris Disk after a Satellite Catastrophic Disruption around Saturn". United States. doi:10.3847/1538-3881/AA74C9.
@article{osti_22663436,
title = {Dynamical Evolution of the Debris Disk after a Satellite Catastrophic Disruption around Saturn},
author = {Hyodo, Ryuki and Charnoz, Sébastien},
abstractNote = {The hypothesis of the recent origin of Saturn’s rings and its midsized moons is actively debated. It was suggested that a proto-Rhea and a proto-Dione might have collided recently, giving birth to the modern system of midsized moons. It has also been suggested that the rapid viscous spreading of the debris may have implanted mass inside Saturn’s Roche limit, giving birth to its modern ring system. However, this scenario has only been investigated in a very simplified way for the moment. This paper investigates it in detail to assess its plausibility by using N -body simulations and analytical arguments. When the debris disk is dominated by its largest remnant, N -body simulations show that the system quickly reaccretes into a single satellite without significant spreading. On the other hand, if the disk is composed of small particles, analytical arguments suggest that the disk experiences dynamical evolutions in three steps. The disk starts significantly excited after the impact and collisional damping dominates over the viscous spreading. After the system flattens, the system can become gravitationally unstable when particles are smaller than ∼100 m. However, the particles grow faster than spreading. Then, the system becomes gravitationally stable again and accretion continues at a slower pace, but spreading is inhibited. Therefore, the debris is expected to reaccrete into several large bodies. In conclusion, our results show that such a scenario may not form today’s ring system. In contrast, our results suggest that today’s midsized moons are likely reaccreted from such a catastrophic event.},
doi = {10.3847/1538-3881/AA74C9},
journal = {Astronomical Journal (Online)},
number = 1,
volume = 154,
place = {United States},
year = {Sat Jul 01 00:00:00 EDT 2017},
month = {Sat Jul 01 00:00:00 EDT 2017}
}
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