Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Gamma-ray lens development status for a European Gamma-Ray Imager   A breakthrough in the sensitivity level of the hard X-/gamma-ray telescopes,
which today are based on detectors that view the sky through (or not) coded
masks, is expected when focusing optics will be available also in this energy
range. Focusing techniques are now in an advanced stage of development. To date
the most efficient technique to focus hard X-rays with energies above 100 keV
appears to be the Bragg diffraction from crystals in transmission configuration
(Laue lenses). Crystals with mosaic structure appear to be the most suitable to
build a Laue lens with a broad passband, even though other alternative
structures are being investigated. The goal of our project is the development
of a broad band focusing telescope based on gamma-ray lenses for the study of
the continuum emission of celestial sources from 60 keV up to >600 keV. We will
report details of our project, its development status and results of our
assessment study of a lens configuration for the European Gamma Ray Imager
(GRI) mission now under study for the ESA plan "Cosmic Vision 2015-2025".

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The categories of this paper are: cond-mat
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The categories of this paper are: gr-qc
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The categories of this paper are: adap-org
1
The categories of this paper are: cs
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The categories of this paper are: math-ph
25
The categories of this paper are: patt-sol
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The categories of this paper are: mtrl-th
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The categories of this paper are: chao-dyn
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The categories of this paper are: chem-ph
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The categories of this paper are: nlin
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The categories of this paper are: quant-ph
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The categories of this paper are: hep-ex
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The categories of this paper are: econ
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The categories of this paper are: hep-th
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The categories of this paper are: atom-ph
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The categories of this paper are: dg-ga