Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Superconductivity-induced changes of the phonon resonances in
  RBa_2Cu_3O_7 (R=rare earth)   We observe a characteristic energy $\hbar\omega_{c}\approx 2.1$ eV which
separates regions of different behavior of the phonon intensities in the Raman
spectra of the $R\rm Ba_2Cu_3O_7$ system. A superconductivity-induced drop of
phonon intensities is found for the oxygen modes O(4) and O(2)-O(3) only for
excitation energies below $\hbar\omega_c$. This intensity drop indicates an
order parameter which affects energies in the vicinity of $\hbar\omega_c$.

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The categories of this paper are: bayes-an
17
The categories of this paper are: q-fin
16
The categories of this paper are: stat
28
The categories of this paper are: alg-geom
27
The categories of this paper are: comp-gas
1
The categories of this paper are: cs
0
The categories of this paper are: hep-ph
20
The categories of this paper are: acc-phys
2
The categories of this paper are: math
21
The categories of this paper are: adap-org
11
The categories of this paper are: hep-lat
37
The categories of this paper are: supr-con
12
The categories of this paper are: nucl-th
6
The categories of this paper are: astro-ph
33
The categories of this paper are: plasm-ph
22
The categories of this paper are: chao-dyn