Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Inelastic neutron scattering due to acoustic vibrations confined in
  nanoparticles: theory and experiment   The inelastic scattering of neutrons by nanoparticles due to acoustic
vibrational modes (energy below 10 meV) confined in nanoparticles is calculated
using the Zemach-Glauber formalism. Such vibrational modes are commonly
observed by light scattering techniques (Brillouin or low-frequency Raman
scattering). We also report high resolution inelastic neutron scattering
measurements for anatase TiO2 nanoparticles in a loose powder. Factors enabling
the observation of such vibrations are discussed. These include a narrow
nanoparticle size distribution which minimizes inhomogeneous broadening of the
spectrum and the presence of hydrogen atoms oscillating with the nanoparticle
surfaces which enhances the number of scattered neutrons.

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The categories of this paper are: solv-int
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The categories of this paper are: nucl-ex
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The categories of this paper are: q-alg
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The categories of this paper are: adap-org
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The categories of this paper are: plasm-ph
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The categories of this paper are: bayes-an
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The categories of this paper are: comp-gas
9
The categories of this paper are: nlin
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The categories of this paper are: patt-sol
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The categories of this paper are: hep-lat
1
The categories of this paper are: cs
34
The categories of this paper are: chem-ph
2
The categories of this paper are: math
3
The categories of this paper are: physics
7
The categories of this paper are: hep-th
31
The categories of this paper are: ao-sci