Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Coexistence of magnetic fluctuations and superconductivity in the
  pnictide high temperature superconductor SmFeAsO$_{1-x}$F$_{x}$ measured by
  muon spin rotation
18
The categories of this paper are: econ
2
The categories of this paper are: math
29
The categories of this paper are: funct-an
37
The categories of this paper are: supr-con
6
The categories of this paper are: astro-ph
21
The categories of this paper are: adap-org
20
The categories of this paper are: acc-phys
27
The categories of this paper are: comp-gas
7
The categories of this paper are: hep-th
16
The categories of this paper are: stat
30
The categories of this paper are: q-alg
13
The categories of this paper are: quant-ph
35
The categories of this paper are: mtrl-th
28
The categories of this paper are: alg-geom
22
The categories of this paper are: chao-dyn
15
The categories of this paper are: nucl-ex