Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Type I and Two-Gap Superconductivity in Neutron Star Magnetism   Neutron-star inner cores with several charged baryonic components are likely
to be analogues of the two-gap superconductor which is of current interest in
condensed-matter physics. Consequently, type I superconductivity is less
probable than type II but may nevertheless be present in some intervals of
matter density. The intermediate state structure formed at finite magnetic flux
densities after the superconducting transitions is subject to buoyancy,
frictional and neutron-vortex interaction forces. These are estimated and it is
shown that the most important frictional force is that produced by the stable
stratification of neutron-star matter, the irreversible process being diffusion
in the normal, finite magnetic-flux density, parts of the structure. The
length-scale of the structure, in directions perpendicular to the local
magnetic field is of crucial importance. For small scales, the flux comoves
with the neutron vortices, as do the proton vortices of a type II
superconductor. But for much larger length-scales, flux movement tends to that
expected for normal charged Fermi systems.

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The categories of this paper are: dg-ga
4
The categories of this paper are: cond-mat
33
The categories of this paper are: plasm-ph
16
The categories of this paper are: stat
30
The categories of this paper are: q-alg
8
The categories of this paper are: hep-ex
18
The categories of this paper are: econ
20
The categories of this paper are: acc-phys
26
The categories of this paper are: bayes-an
15
The categories of this paper are: nucl-ex
14
The categories of this paper are: math-ph
0
The categories of this paper are: hep-ph
28
The categories of this paper are: alg-geom
29
The categories of this paper are: funct-an
19
The categories of this paper are: eess
31
The categories of this paper are: ao-sci