Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quark Deconfinement in Rotating Neutron Stars   In this paper, we use a three flavor non-local Nambu--Jona-Lasinio (NJL)
model, an~improved effective model of Quantum Chromodynamics (QCD) at low
energies, to investigate the existence of deconfined quarks in the cores of
neutron stars. Particular emphasis is put on the possible existence of quark
matter in the cores of rotating neutron stars (pulsars). In contrast to
non-rotating neutron stars, whose particle compositions do not change with time
(are frozen in), the type and structure of the matter in the cores of rotating
neutron stars depends on the spin frequencies of these stars, which opens up a
possible new window on the nature of matter deep in the cores of neutron stars.
Our study shows that, depending on mass and rotational frequency, up to around
8% of the mass of a massive neutron star may be in the mixed quark-hadron
phase, if the phase transition is treated as a Gibbs transition. We also find
that the gravitational mass at which quark deconfinement occurs in rotating
neutron stars varies quadratically with spin frequency, which can be fitted by
a simple formula.

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The categories of this paper are: cond-mat
1
The categories of this paper are: cs
9
The categories of this paper are: nlin
29
The categories of this paper are: funct-an
2
The categories of this paper are: math
8
The categories of this paper are: hep-ex
11
The categories of this paper are: hep-lat
30
The categories of this paper are: q-alg
31
The categories of this paper are: ao-sci
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The categories of this paper are: gr-qc
37
The categories of this paper are: supr-con
17
The categories of this paper are: q-fin
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The categories of this paper are: physics
35
The categories of this paper are: mtrl-th
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The categories of this paper are: adap-org
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The categories of this paper are: cmp-lg