Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: THz spectroscopy in the pseudo-Kagome system Cu3Bi(SeO3)2O2Br   Terahertz (THz) transmission spectra have been measured as function of
temperature and magnetic field on single crystals of Cu3Bi(SeO3)2O2Br. In the
time-domain THz spectra without magnetic field, two resonance absorptions are
observed below the magnetic ordering temperature T_N~27.4 K. The corresponding
resonance frequencies increase with decreasing temperature and reach energies
of 1.28 and 1.23 meV at 3.5 K. Multi-frequency electron spin resonance
transmission spectra as a function of applied magnetic field show the field
dependence of four magnetic resonance modes, which can be modeled as a
ferromagnetic resonance including demagnetization and anisotropy effects.

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The categories of this paper are: astro-ph
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The categories of this paper are: adap-org
32
The categories of this paper are: atom-ph
25
The categories of this paper are: patt-sol
3
The categories of this paper are: physics
8
The categories of this paper are: hep-ex
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The categories of this paper are: hep-ph
37
The categories of this paper are: supr-con
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The categories of this paper are: solv-int
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The categories of this paper are: bayes-an
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The categories of this paper are: nucl-ex
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The categories of this paper are: hep-lat
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The categories of this paper are: nucl-th
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The categories of this paper are: dg-ga
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The categories of this paper are: chao-dyn
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The categories of this paper are: alg-geom