Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Particles trajectories in magnetic filaments   The motion of a particle in a spatially harmonic magnetic field is a basic
problem involved, for example, in the mechanism of formation of a collisionless
shock. In such settings, it is generally reasoned that particles entering a
Weibel generated turbulence are trapped inside it, provided their Larmor radius
in the peak field is smaller than the field coherence length. The goal of this
work is to put this heuristic conclusion on firm ground by studying, both
analytically and numerically, such motion. A toy model is analyzed, consisting
of a relativistic particle entering a region of space occupied by a spatially
harmonic field. The particle penetrates the magnetic structure in a direction
aligned with the magnetic filaments. Although the conclusions are not trivial,
the main result is confirmed.

10
The categories of this paper are: q-bio
4
The categories of this paper are: cond-mat
11
The categories of this paper are: hep-lat
21
The categories of this paper are: adap-org
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The categories of this paper are: nucl-ex
18
The categories of this paper are: econ
33
The categories of this paper are: plasm-ph
34
The categories of this paper are: chem-ph
32
The categories of this paper are: atom-ph
2
The categories of this paper are: math
26
The categories of this paper are: bayes-an
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The categories of this paper are: q-fin
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The categories of this paper are: alg-geom
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The categories of this paper are: math-ph
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The categories of this paper are: nlin
36
The categories of this paper are: cmp-lg