Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Neutrino Emission from Neutron Stars   We review the main neutrino emission mechanisms in neutron star crusts and
cores. Among them are the well-known reactions such as the electron-positron
annihilation, plasmon decay, neutrino bremsstrahlung of electrons colliding
with atomic nuclei in the crust, as well as the Urca processes and neutrino
bremsstrahlung in nucleon-nucleon collisions in the core. We emphasize recent
theoretical achievements, for instance, band structure effects in neutrino
emission due to scattering of electrons in Coulomb crystals of atomic nuclei.
We consider the standard composition of matter (neutrons, protons, electrons,
muons, hyperons) in the core, and also the case of exotic constituents such as
the pion or kaon condensates and quark matter. We discuss the reduction of the
neutrino emissivities by nucleon superfluidity, as well as the specific
neutrino emission produced by Cooper pairing of the superfluid particles. We
also analyze the effects of strong magnetic fields on some reactions, such as
the direct Urca process and the neutrino synchrotron emission of electrons. The
results are presented in the form convenient for practical use. We illustrate
the effects of various neutrino reactions on the cooling of neutron stars. In
particular, the neutrino emission in the crust is critical in setting the
initial thermal relaxation between the core and the crust. Finally, we discuss
the prospects of exploring the properties of supernuclear matter by confronting
cooling simulations with observations of the thermal radiation from isolated
neutron stars.

31
The categories of this paper are: ao-sci
25
The categories of this paper are: patt-sol
11
The categories of this paper are: hep-lat
17
The categories of this paper are: q-fin
33
The categories of this paper are: plasm-ph
18
The categories of this paper are: econ
29
The categories of this paper are: funct-an
16
The categories of this paper are: stat
3
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: alg-geom
10
The categories of this paper are: q-bio
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The categories of this paper are: eess
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The categories of this paper are: supr-con
32
The categories of this paper are: atom-ph
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The categories of this paper are: chem-ph