Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Radial Orbit Instability in Collisionless N-Body Simulations   Using a suite of self-gravitating, collisionless N-body models, we
systematically explore a parameter space relevant to the onset and behavior of
the radial orbit instability (ROI), whose strength is measured by the systemic
axis ratios of the models. We show that a combination of two initial
conditions, namely the velocity anisotropy and the virial ratio, determines
whether a system will undergo ROI and exactly how triaxial the system will
become. A third initial condition, the radial shape of the density profile,
plays a smaller, but noticeable role. Regarding the dynamical development of
the ROI, the instability a) begins after systems collapse to their most compact
configuration and b) evolves fastest when a majority of the particles have
radially anisotropic orbits while there is a lack of centrally-concentrated
isotropic orbits. We argue that this is further evidence that self-reinforcing
torques are the key to the onset of the ROI. Our findings support the idea that
a separate orbit instability plays a role in halting the ROI.

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The categories of this paper are: hep-ex
33
The categories of this paper are: plasm-ph
12
The categories of this paper are: nucl-th
24
The categories of this paper are: dg-ga
25
The categories of this paper are: patt-sol
27
The categories of this paper are: comp-gas
7
The categories of this paper are: hep-th
17
The categories of this paper are: q-fin
2
The categories of this paper are: math
10
The categories of this paper are: q-bio
16
The categories of this paper are: stat
9
The categories of this paper are: nlin
18
The categories of this paper are: econ
28
The categories of this paper are: alg-geom
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The categories of this paper are: funct-an
35
The categories of this paper are: mtrl-th