Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Dense planetary rings and the viscous overstability   This paper examines the onset of the viscous overstability in dense
particulate rings. First, we formulate a dense gas kinetic theory that is
applicable to the Saturnian system. Our model is essentially that of Araki and
Tremaine (1986), which we show can be both simplified and generalised. Second,
we put this model to work computing the equilibrium properties of dense
planetary rings, which we subsequently compare with the results of N-body
simulations, namely those of Salo (1991). Finally, we present the linear
stability analyses of these equilibrium states, and derive criteria for the
onset of viscous overstability in the self-gravitating and non-self-gravitating
cases. These are framed in terms of particle size, orbital frequency, optical
depth, and the parameters of the collision law. Our results compare favourably
with the simulations of Salo et al. (2001). The accuracy and practicality of
the continuum model we develop encourages its general use in future
investigations of nonlinear phenomena.

3
The categories of this paper are: physics
35
The categories of this paper are: mtrl-th
31
The categories of this paper are: ao-sci
19
The categories of this paper are: eess
8
The categories of this paper are: hep-ex
32
The categories of this paper are: atom-ph
11
The categories of this paper are: hep-lat
5
The categories of this paper are: gr-qc
26
The categories of this paper are: bayes-an
9
The categories of this paper are: nlin
24
The categories of this paper are: dg-ga
17
The categories of this paper are: q-fin
12
The categories of this paper are: nucl-th
0
The categories of this paper are: hep-ph
1
The categories of this paper are: cs
21
The categories of this paper are: adap-org