Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Spin correlations in an isotropic spin-5/2 two-dimensional
  antiferromagnet   We report a neutron scattering study of the spin correlations for the spin
5/2, two-dimensional antiferromagnet Rb_2MnF_4 in an external magnetic field.
Choosing fields near the system's bicritical point, we tune the effective
anisotropy in the spin interaction to zero, constructing an ideal S=5/2
Heisenberg system. The correlation length and structure factor amplitude are
closely described by the semiclassical theory of Cuccoli et al. over a broad
temperature range but show no indication of approaching the low-temperature
renormalized classical regime of the quantum non-linear sigma model.

6
The categories of this paper are: astro-ph
8
The categories of this paper are: hep-ex
15
The categories of this paper are: nucl-ex
0
The categories of this paper are: hep-ph
29
The categories of this paper are: funct-an
33
The categories of this paper are: plasm-ph
35
The categories of this paper are: mtrl-th
2
The categories of this paper are: math
34
The categories of this paper are: chem-ph
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The categories of this paper are: acc-phys
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The categories of this paper are: comp-gas
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The categories of this paper are: stat
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The categories of this paper are: chao-dyn
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The categories of this paper are: supr-con
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The categories of this paper are: eess
28
The categories of this paper are: alg-geom