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Physical Sciences and Mathematics Commons

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Astrophysics and Astronomy

University of Nevada, Las Vegas

Series

2018

Methods: Numerical

Articles 1 - 2 of 2

Full-Text Articles in Physical Sciences and Mathematics

Streaming Instability Of Multiple Particle Species In Protoplanetary Disks, Noemi Schaffer, Chao-Chin Yang, Anders Johansen Oct 2018

Streaming Instability Of Multiple Particle Species In Protoplanetary Disks, Noemi Schaffer, Chao-Chin Yang, Anders Johansen

Physics & Astronomy Faculty Research

The radial drift and diffusion of dust particles in protoplanetary disks affect both the opacity and temperature of such disks, as well as the location and timing of planetesimal formation. In this paper, we present results of numerical simulations of particle-gas dynamics in protoplanetary disks that include dust grains with various size distributions. We have considered three scenarios in terms of particle size ranges, one where the Stokes number τs = 10−1−100, one where τs = 10−4−10−1, and finally one where τs= 10−3−100. Moreover, we considered both discrete and continuous distributions in particle size. In accordance with previous works we …


Survival Of Non-Coplanar, Closely Packed Planetary Systems After A Close Encounter, David R. Rice, Frederic A. Rasio, Jason H. Steffen Sep 2018

Survival Of Non-Coplanar, Closely Packed Planetary Systems After A Close Encounter, David R. Rice, Frederic A. Rasio, Jason H. Steffen

Physics & Astronomy Faculty Research

Planetary systems with more than two bodies will experience orbital crossings at a time related to the initial orbital separations of the planets. After a crossing, the system enters a period of chaotic evolution ending in the reshaping of the system’s architecture via planetary collisions or ejections. We carry out N-body integrations on a large number of systems with equally spaced planets (in units of the Hill radius) to determine the distribution of instability times for a given planet separation. We investigate both the time to the initiation of instability through a close encounter and the time to a planet--planet …