Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Drift Orbit Bifurcations and Cross-field Transport in the Outer
  Radiation Belt: Global MHD and Integrated Test-Particle Simulations   Energetic particle fluxes in the outer magnetosphere present a significant
challenge to modelling efforts as they can vary by orders of magnitude in
response to solar wind driving conditions. In this article, we demonstrate the
ability to propagate test particles through global MHD simulations to a high
level of precision and use this to map the cross-field radial transport
associated with relativistic electrons undergoing drift orbit bifurcations
(DOBs). The simulations predict DOBs primarily occur within an Earth radius of
the magnetopause loss cone and appears significantly different for southward
and northward interplanetary magnetic field orientations. The changes to the
second invariant are shown to manifest as a dropout in particle fluxes with
pitch angles close to 90$^\circ$ and indicate DOBs are a cause of butterfly
pitch angle distributions within the night-time sector. The convective electric
field, not included in previous DOB studies, is found to have a significant
effect on the resultant long term transport, and losses to the magnetopause and
atmosphere are identified as a potential method for incorporating DOBs within
Fokker-Planck transport models.

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The categories of this paper are: hep-th
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The categories of this paper are: acc-phys
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The categories of this paper are: alg-geom
35
The categories of this paper are: mtrl-th
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The categories of this paper are: nlin
36
The categories of this paper are: cmp-lg
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The categories of this paper are: gr-qc
34
The categories of this paper are: chem-ph
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The categories of this paper are: solv-int
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The categories of this paper are: adap-org
27
The categories of this paper are: comp-gas
18
The categories of this paper are: econ
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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: stat
29
The categories of this paper are: funct-an