Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Highly Sensitive Gamma-Spectrometers of GERDA for Material Screening:
  Part 2   The previous article about material screening for GERDA points out the
importance of strict material screening and selection for radioimpurities as a
key to meet the aspired background levels of the GERDA experiment. This is
directly done using low-level gamma-spectroscopy. In order to provide
sufficient selective power in the mBq/kg range and below, the employed
gamma-spectrometers themselves have to meet strict material requirements, and
make use of an elaborate shielding system. This article gives an account of the
setup of two such spectrometers. Corrado is located in a depth of 15 m w.e. at
the MPI-K in Heidelberg (Germany), GeMPI III is situated at the Gran-Sasso
underground laboratory at 3500 m w.e. (Italy). The latter one aims at detecting
sample activities of the order ~0.01 mBq/kg, which is the current
state-of-the-art level. The applied techniques to meet the respective needs are
discussed and demonstrated by experimental results.

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The categories of this paper are: patt-sol
34
The categories of this paper are: chem-ph
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The categories of this paper are: quant-ph
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The categories of this paper are: acc-phys
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The categories of this paper are: stat
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The categories of this paper are: cmp-lg
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The categories of this paper are: adap-org
4
The categories of this paper are: cond-mat
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The categories of this paper are: solv-int
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The categories of this paper are: q-alg
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The categories of this paper are: alg-geom
12
The categories of this paper are: nucl-th
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The categories of this paper are: atom-ph
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The categories of this paper are: astro-ph
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The categories of this paper are: hep-lat
1
The categories of this paper are: cs