Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Particle energization through time-periodic helical magnetic fields   We solve for the motion of charged particles in a helical time-periodic ABC
(Arnold-Beltrami-Childress) magnetic field. The magnetic field lines of a
stationary ABC field with coefficients $A=B=C=1$ are chaotic, and we show that
the motion of a charged particle in such a field is also chaotic at late times
with positive Lyapunov exponent. We further show that in time-periodic ABC
fields, the kinetic energy of a charged particle can increase indefinitely with
time. At late times the mean kinetic energy grows as a power law in time with
an exponent that approaches unity. For an initial distribution of particles,
whose kinetic energy is uniformly distributed within some interval, the PDF of
kinetic energy is, at late times, close to a Gaussian but with steeper tails.

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The categories of this paper are: bayes-an
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The categories of this paper are: q-alg
5
The categories of this paper are: gr-qc
11
The categories of this paper are: hep-lat
1
The categories of this paper are: cs
34
The categories of this paper are: chem-ph
18
The categories of this paper are: econ
16
The categories of this paper are: stat
8
The categories of this paper are: hep-ex
35
The categories of this paper are: mtrl-th
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The categories of this paper are: supr-con
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The categories of this paper are: patt-sol
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The categories of this paper are: math-ph
22
The categories of this paper are: chao-dyn
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The categories of this paper are: funct-an
0
The categories of this paper are: hep-ph