Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Microwave response of a cylindrical cavity made of bulk MgB2
  superconductor   We report on the microwave properties of a resonant cylindrical cavity made
of bulk MgB2 superconductor, produced by the reactive liquid Mg infiltration
process. The frequency response of the cavity has been measured in the range
5-13GHz. Among the various modes, the TE011, resonating at 9.79GHz, exhibits
the highest quality factor. For this mode, we have determined the temperature
dependence of the quality factor, obtaining values of the order of 10^5 in the
temperature range 4.2-30K. The values of the surface resistance deduced from
the measurements of the quality factor agree quite well with those
independently measured in a small sample of MgB2 extracted from the same
specimen from which the cavity has been obtained.

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The categories of this paper are: patt-sol
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The categories of this paper are: adap-org
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The categories of this paper are: atom-ph
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The categories of this paper are: dg-ga
3
The categories of this paper are: physics
12
The categories of this paper are: nucl-th
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The categories of this paper are: hep-lat
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The categories of this paper are: alg-geom
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The categories of this paper are: ao-sci
1
The categories of this paper are: cs
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The categories of this paper are: nucl-ex
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The categories of this paper are: funct-an
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The categories of this paper are: comp-gas
10
The categories of this paper are: q-bio
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The categories of this paper are: econ
37
The categories of this paper are: supr-con