Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: GRI: focusing on the evolving violent Universe   The Gamma-Ray Imager (GRI) is a novel mission concept that will provide an
unprecedented sensitivity leap in the soft gamma-ray domain by using for the
first time a focusing lens built of Laue diffracting crystals. The lens will
cover an energy band from 200 - 1300 keV with an effective area reaching 600
cm2. It will be complemented by a single reflection multilayer coated mirror,
extending the GRI energy band into the hard X-ray regime, down to ~10 keV. The
concentrated photons will be collected by a position sensitive pixelised CZT
stack detector. We estimate continuum sensitivities of better than 10^-7
ph/cm2/s/keV for a 100 ks exposure; the narrow line sensitivity will be better
than 3 x 10^-6 ph/cm2/s for the same integration time. As focusing instrument,
GRI will have an angular resolution of better than 30 arcsec within a field of
view of roughly 5 arcmin - an unprecedented achievement in the gamma-ray
domain. Owing to the large focal length of 100 m of the lens and the mirror,
the optics and detector will be placed on two separate spacecrafts flying in
formation in a high elliptical orbit. R&D work to enable the lens focusing
technology and to develop the required focal plane detector is currently
underway, financed by ASI, CNES, ESA, and the Spanish Ministery of Education
and Science. The GRI mission is proposed as class M mission for ESA's Cosmic
Vision 2015-2025 program. GRI will allow studies of particle acceleration
processes and explosion physics in unprecedented detail, providing essential
clues on the innermost nature of the most violent and most energetic processes
in the Universe.

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The categories of this paper are: plasm-ph
21
The categories of this paper are: adap-org
27
The categories of this paper are: comp-gas
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The categories of this paper are: chem-ph
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The categories of this paper are: mtrl-th
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The categories of this paper are: hep-ex
2
The categories of this paper are: math
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The categories of this paper are: supr-con
15
The categories of this paper are: nucl-ex
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The categories of this paper are: ao-sci
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The categories of this paper are: q-alg
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The categories of this paper are: dg-ga
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The categories of this paper are: nlin
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The categories of this paper are: cond-mat
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The categories of this paper are: math-ph
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The categories of this paper are: q-fin