Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Antiferromagnetic Critical Fluctuations in BaFe$_2$As$_2$   Magnetic correlations near the magneto-structural phase transition in the
bilayer iron pnictide parent compound, BaFe$_2$As$_2$, are measured. In close
proximity to the antiferromagnetic phase transition in BaFe$_2$As$_2$, a
crossover to three dimensional critical behavior is anticipated and has been
preliminarily observed. Here we report complementary measurements of
two-dimensional magnetic fluctuations over a broad temperature range about
T$_N$. The potential role of two-dimensional critical fluctuations in the
magnetic phase behavior of BaFe$_2$As$_2$ and their evolution near the
anticipated crossover to three dimensional critical behavior and long-range
order are discussed.

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The categories of this paper are: alg-geom
2
The categories of this paper are: math
7
The categories of this paper are: hep-th
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The categories of this paper are: acc-phys
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The categories of this paper are: stat
13
The categories of this paper are: quant-ph
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The categories of this paper are: atom-ph
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The categories of this paper are: econ
1
The categories of this paper are: cs
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The categories of this paper are: ao-sci
14
The categories of this paper are: math-ph
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The categories of this paper are: cmp-lg
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The categories of this paper are: supr-con
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The categories of this paper are: nlin
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The categories of this paper are: q-fin
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The categories of this paper are: funct-an