Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Vibrations of free and embedded anisotropic elastic spheres: Application
  to low-frequency Raman scattering of silicon nanoparticles in silica   Vibrational mode frequencies and damping are calculated for an elastic sphere
embedded in an infinite, homogeneous, isotropic elastic medium. Anisotropic
elasticity of the sphere significantly shifts the frequencies in comparison to
simplified calculations that assume isotropy. New low frequency Raman light
scattering data are presented for silicon spheres grown in a SiO2 glass matrix.
Principal features of the Raman spectrum are not correctly described by a
simple model of the nanoparticle as a free, isotropic sphere, but require both
matrix effects and the anisotropy of the silicon to be taken into account.
Libration, not vibration, is the dominant mechanism.

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The categories of this paper are: nlin
5
The categories of this paper are: gr-qc
28
The categories of this paper are: alg-geom
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The categories of this paper are: econ
13
The categories of this paper are: quant-ph
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The categories of this paper are: acc-phys
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The categories of this paper are: dg-ga
14
The categories of this paper are: math-ph
34
The categories of this paper are: chem-ph
10
The categories of this paper are: q-bio
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The categories of this paper are: hep-ex
15
The categories of this paper are: nucl-ex
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The categories of this paper are: cmp-lg
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The categories of this paper are: q-fin
1
The categories of this paper are: cs
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The categories of this paper are: eess