Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Variations in the pickup ion density structure in response to the growth
  of the Kelvin--Helmholtz instability along the heliopause   Features of the response of pickup ions (PUIs) to the Kelvin--Helmholtz
instability (KHI) on the heliopause (HP) are examined by means of
two-dimensional hybrid simulations. We assume the supersonic neutral solar wind
as the source of PUIs gyrating about the magnetic field in the outer
heliosheath. These PUIs become energetic neutral atoms (ENAs) via charge
exchange with interstellar hydrogen, and a portion of these ENAs are detected
by spacecraft such as the Interstellar Boundary Explorer (IBEX}. To evaluate
the possibility of identifying the KHI on HP from ENA observations, we assume
that an imprint of the KHI may be displayed in spatial and temporal variations
in the observed ENA profile. As an alternative to ENA, the column density of
PUIs integrated across the HP is calculated. The KH-inducing vortex forces not
only background protons but also PUIs to roll up deep in the inner heliosheath.
The KH vortex also results in the emission of magnetosonic pulses that sweep
PUIs in the outer heliosheath and lead to their local confinement. These
effects elongate the PUIs spatial distribution in the direction normal to the
HP. The appearance of the local confined structure in the PUIs column density
is consequently confirmed, and this feature can be confirmed as the KHI
evolution. Although the simulation cannot be quantitatively compared with the
observations currently available because its resolution is too small, we expect
that the derived properties will be useful for diagnosing the nature of HP
fluctuation in future missions.

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The categories of this paper are: hep-ex
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The categories of this paper are: cond-mat
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The categories of this paper are: chem-ph
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The categories of this paper are: econ
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The categories of this paper are: hep-lat
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The categories of this paper are: stat
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The categories of this paper are: bayes-an
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The categories of this paper are: math-ph
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The categories of this paper are: hep-ph
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The categories of this paper are: ao-sci
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The categories of this paper are: quant-ph
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The categories of this paper are: plasm-ph
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The categories of this paper are: eess
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The categories of this paper are: funct-an
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The categories of this paper are: math
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The categories of this paper are: solv-int