Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Thermal and surface anisotropy effects on the magnetization reversal of
  a nanocluster   The relaxation rate and temperature-dependent switching field curve of a
spherical magnetic nanocluster are calculated by taking into account the effect
of surface anisotropy via an effective anisotropy model. In particular, it is
shown that surface anisotropy may change the thermally activated magnetization
reversal by more than an order of magnitude, and that temperature-dependent
switching field curves noticeably deviate from the Stoner-Wohlfarth astroid.
With recent and future $\mu$-SQUID measurements in mind, we indicate how
comparison of our results with experimental data on isolated clusters may allow
one to obtain valuable information on surface anisotropy.

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The categories of this paper are: chao-dyn
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The categories of this paper are: hep-th
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The categories of this paper are: astro-ph
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The categories of this paper are: solv-int
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The categories of this paper are: math-ph
3
The categories of this paper are: physics
31
The categories of this paper are: ao-sci
37
The categories of this paper are: supr-con
29
The categories of this paper are: funct-an
34
The categories of this paper are: chem-ph
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The categories of this paper are: plasm-ph
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The categories of this paper are: econ
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The categories of this paper are: eess
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The categories of this paper are: alg-geom
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The categories of this paper are: adap-org
1
The categories of this paper are: cs