Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Effect of Fermi Surface Nesting on Resonant Spin Excitations in
  Ba1-xKxFe2As2   We report inelastic neutron scattering measurements of the resonant spin
excitations in Ba1-xKxFe2As2 over a broad range of electron band filling. The
fall in the superconducting transi- tion temperature with hole doping coincides
with the magnetic excitations splitting into two incom- mensurate peaks because
of the growing mismatch in the hole and electron Fermi surface volumes, as
confirmed by a tight-binding model with s+- symmetry pairing. The reduction in
Fermi surface nesting is accompanied by a collapse of the resonance binding
energy and its spectral weight caused by the weakening of electron-electron
correlations.

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The categories of this paper are: stat
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The categories of this paper are: physics
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The categories of this paper are: nlin
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The categories of this paper are: nucl-th
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The categories of this paper are: patt-sol
2
The categories of this paper are: math
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The categories of this paper are: econ
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The categories of this paper are: eess
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The categories of this paper are: hep-th
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The categories of this paper are: quant-ph
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The categories of this paper are: hep-ex
33
The categories of this paper are: plasm-ph
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The categories of this paper are: q-bio
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The categories of this paper are: ao-sci
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The categories of this paper are: dg-ga
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The categories of this paper are: gr-qc