Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Magnetic Energy Conversion in MHD: Curvature Relaxation and
  Perpendicular Expansion of Magnetic Fields   The mechanisms and pathways of magnetic energy conversion are an important
subject for many laboratory, space and astrophysical systems. Here, we present
a perspective on magnetic energy conversion in MHD through magnetic field
curvature relaxation (CR) and perpendicular expansion (PE) due to magnetic
pressure gradients, and quantify their relative importance in two
representative cases, namely 3D magnetic reconnection and 3D kink-driven
instability in an astrophysical jet. We find that the CR and PE processes have
different temporal and spatial evolution in these systems. The relative
importance of the two processes tends to reverse as the system enters the
nonlinear stage from the instability growth stage. Overall, the two processes
make comparable contributions to the magnetic energy conversion with the PE
process somewhat stronger than the CR process. We further explore how these
energy conversion terms can be related to particle energization in these
systems.

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The categories of this paper are: eess
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The categories of this paper are: comp-gas
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The categories of this paper are: mtrl-th
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The categories of this paper are: funct-an
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The categories of this paper are: patt-sol
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The categories of this paper are: solv-int
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The categories of this paper are: adap-org
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The categories of this paper are: q-fin
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The categories of this paper are: stat
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The categories of this paper are: q-alg
0
The categories of this paper are: hep-ph
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The categories of this paper are: hep-ex
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The categories of this paper are: math
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The categories of this paper are: bayes-an
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The categories of this paper are: acc-phys
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The categories of this paper are: atom-ph