Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Propagation and dispersion of sausage wave trains in magnetic flux tubes   A localized perturbation of a magnetic flux tube produces a pair of wave
trains that propagate in opposite directions along the tube. These wave packets
disperse as they propagate, where the extent of dispersion depends on the
physical properties of the magnetic structure, on the length of the initial
excitation, and on its nature (e.g., transverse or axisymmetric). In Oliver et
al. (2014) we considered a transverse initial perturbation, whereas the
temporal evolution of an axisymmetric one is examined here. In both papers we
use a method based on Fourier integrals to solve the initial value problem.
Previous studies on wave propagation in magnetic wave guides have emphasized
that the wave train dispersion is influenced by the particular dependence of
the group velocity on the longitudinal wavenumber. Here we also find that long
initial perturbations result in low amplitude wave packets and that large
values of the magnetic tube to environment density ratio yield longer wave
trains. To test the detectability of propagating transverse or axisymmetric
wave packets in magnetic tubes of the solar atmosphere (e.g., coronal loops,
spicules, or prominence threads) a forward modelling of the perturbations must
be carried out. This is left for a future work.

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The categories of this paper are: acc-phys
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The categories of this paper are: stat
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The categories of this paper are: q-fin
33
The categories of this paper are: plasm-ph
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The categories of this paper are: nucl-th
9
The categories of this paper are: nlin
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The categories of this paper are: adap-org
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The categories of this paper are: patt-sol
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The categories of this paper are: hep-lat
7
The categories of this paper are: hep-th
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The categories of this paper are: nucl-ex
35
The categories of this paper are: mtrl-th
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The categories of this paper are: physics
32
The categories of this paper are: atom-ph
5
The categories of this paper are: gr-qc
8
The categories of this paper are: hep-ex