Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The role of compressibility in solar wind plasma turbulence   Incompressible Magnetohydrodynamics is often assumed to describe solar wind
turbulence. We use extended self similarity to reveal scaling in structure
functions of density fluctuations in the solar wind. Obtained scaling is then
compared with that found in the inertial range of quantities identified as
passive scalars in other turbulent systems. We find that these are not
coincident. This implies that either solar wind turbulence is compressible, or
that straightforward comparison of structure functions does not adequately
capture its inertial range properties.

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The categories of this paper are: stat
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The categories of this paper are: adap-org
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The categories of this paper are: nucl-ex
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The categories of this paper are: q-fin
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The categories of this paper are: chem-ph
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The categories of this paper are: nucl-th
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The categories of this paper are: quant-ph
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The categories of this paper are: physics
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The categories of this paper are: chao-dyn
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The categories of this paper are: plasm-ph
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The categories of this paper are: hep-th
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The categories of this paper are: solv-int
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The categories of this paper are: gr-qc
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The categories of this paper are: cmp-lg
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The categories of this paper are: supr-con
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The categories of this paper are: atom-ph