Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Bulk viscosity of strange matter and r-modes in neutron stars   We discuss bulk viscosity due to non-leptonic processes involving hyperons
and Bose-Einstein condensate of negatively charged kaons in neutron stars. It
is noted that the hyperon bulk viscosity coefficient is a few order of
magnitude larger than that of the case with the condensate. Further it is found
that the hyperon bulk viscosity is suppressed in a superconducting phase. The
hyperon bulk viscosity efficiently damps the r-mode instability in neutron
stars irrespective of whether a superconducting phase is present or not in
neutron star interior.

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The categories of this paper are: quant-ph
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The categories of this paper are: dg-ga
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The categories of this paper are: hep-lat
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The categories of this paper are: chao-dyn
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The categories of this paper are: funct-an
7
The categories of this paper are: hep-th
4
The categories of this paper are: cond-mat
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The categories of this paper are: eess
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The categories of this paper are: acc-phys
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The categories of this paper are: math
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The categories of this paper are: nucl-ex
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The categories of this paper are: gr-qc
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The categories of this paper are: patt-sol
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The categories of this paper are: cs
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The categories of this paper are: chem-ph
3
The categories of this paper are: physics