Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Impact of Fission Neutron Energies on Reactor Antineutrino Spectra   Recent measurements of reactor-produced antineutrino fluxes and energy
spectra are inconsistent with models based on measured thermal fission beta
spectra. In this paper, we examine the dependence of antineutrino production on
fission neutron energy. In particular, the variation of fission product yields
with neutron energy has been considered as a possible source of the
discrepancies between antineutrino observations and models. In simulations of
low-enriched and highly-enriched reactor core designs, we find a substantial
fraction of fissions (from 5% to more than 40%) are caused by non-thermal
neutrons. Using tabulated evaluations of nuclear fission and decay, we estimate
the variation in antineutrino emission by the prominent fission parents U-235,
Pu-239, and Pu-241 versus neutron energy. The differences in fission neutron
energy are found to produce less than 1% variation in detected antineutrino
rate per fission of U-235, Pu-239, and Pu-241. Corresponding variations in the
antineutrino spectrum are found to be less than 10% below 7 MeV antineutrino
energy, smaller than current model uncertainties. We conclude that insufficient
modeling of fission neutron energy is unlikely to be the cause of the various
reactor anomalies. Our results also suggest that comparisons of antineutrino
measurements at low-enriched and highly-enriched reactors can safely neglect
the differences in the distributions of their fission neutron energies.

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The categories of this paper are: eess
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The categories of this paper are: cmp-lg
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The categories of this paper are: funct-an
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The categories of this paper are: gr-qc
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The categories of this paper are: solv-int
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The categories of this paper are: math
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The categories of this paper are: ao-sci
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The categories of this paper are: hep-ph
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The categories of this paper are: astro-ph
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The categories of this paper are: physics
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The categories of this paper are: mtrl-th
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The categories of this paper are: dg-ga
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The categories of this paper are: cs
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The categories of this paper are: adap-org
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The categories of this paper are: q-bio
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The categories of this paper are: patt-sol