Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Inelastic neutron scattering study on the resonance mode in an optimally
  doped superconductor LaFeAsO$_{0.92}$F$_{0.08}$   An optimally doped iron-based superconductor LaFeAsO$_{0.92}$F$_{0.08}$ with
$T_c = 29$ K has been studied by inelastic powder neutron scattering. The
magnetic excitation at $Q=1.15$ \AA$^{-1}$ is enhanced below $T_c$, leading to
a peak at $E_{res}\sim13$ meV as the resonance mode, in addition to the
formation of a gap at low energy below the crossover energy $\Delta_{c}\sim10
meV$. The peak energy at $Q=1.15$ \AA$^{-1}$ corresponds to $5.2 k_B T_c$ in
good agreement with the other values of resonance mode observed in the various
iron-based superconductors, even in the high-$T_c$ cuprates. Although the
phonon density of states has a peak at the same energy as the resonance mode in
the present superconductor, the $Q$-dependence is consistent with the resonance
being of predominately magnetic origin.

6
The categories of this paper are: astro-ph
18
The categories of this paper are: econ
27
The categories of this paper are: comp-gas
33
The categories of this paper are: plasm-ph
13
The categories of this paper are: quant-ph
19
The categories of this paper are: eess
20
The categories of this paper are: acc-phys
30
The categories of this paper are: q-alg
34
The categories of this paper are: chem-ph
26
The categories of this paper are: bayes-an
3
The categories of this paper are: physics
21
The categories of this paper are: adap-org
15
The categories of this paper are: nucl-ex
16
The categories of this paper are: stat
1
The categories of this paper are: cs
32
The categories of this paper are: atom-ph