Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Heavy fermion superconductivity in the filled skutterudite compound
  PrOs$_4$Sb$_{12}$   The filled skutterudite compound \PrOsSb{} has been found to exhibit
superconductivity with a critical temperature $T_\mathrm{c} = 1.85$ K that
develops out of a heavy Fermi liquid with an effective mass $m^{*} \approx 50
m_\mathrm{e}$. The current experimental situation regarding the heavy fermion
state, the superconducting state, and a high field, low temperature phase that
is apparently associated with magnetic or quadrupolar order in \PrOsSb{} is
briefly reviewed herein.

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The categories of this paper are: atom-ph
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The categories of this paper are: ao-sci
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The categories of this paper are: mtrl-th
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The categories of this paper are: gr-qc
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The categories of this paper are: acc-phys
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The categories of this paper are: nucl-ex
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The categories of this paper are: math-ph
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The categories of this paper are: nlin
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The categories of this paper are: stat
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The categories of this paper are: comp-gas
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The categories of this paper are: dg-ga
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The categories of this paper are: nucl-th
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The categories of this paper are: cs
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The categories of this paper are: econ
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The categories of this paper are: chao-dyn
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The categories of this paper are: cmp-lg