Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: MAGIC measurement of the Crab Nebula spectrum over three decades in
  energy   The Crab Pulsar Wind Nebula is the best studied source of $\gamma$-ray
astrophysics. The contribution of the various soft radiation fields to the
Inverse Compton component of its high energy emission, the strenght of the
internal magnetic field and the maximum energies reached by primary electrons
are however still matter of study. The MAGIC stereoscopic system recorded
almost 50 hours of Crab Nebula data in the last two years, between October 2009
and April 2011. Analysis of this data sample using the latest improvements in
the MAGIC stereo software provided an unprecedented differential energy
spectrum spanning three decades in energy, from 50 GeV up to 45 TeV. At low
energies, the MAGIC results, combined with the Fermi/LAT data, yield a precise
measurement of the Inverse Compton peak. In addition, we present light curves
of the Crab Nebula at different time scales, including a measurement
simultaneous to one of the Crab Nebula flares recently detected by both
Fermi/LAT and AGILE. Using the MAGIC spectrum together with multiwavelength
data, we discuss the implications for the modeling of the Crab Nebula.

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The categories of this paper are: plasm-ph
4
The categories of this paper are: cond-mat
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The categories of this paper are: funct-an
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The categories of this paper are: hep-lat
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The categories of this paper are: hep-th
3
The categories of this paper are: physics
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The categories of this paper are: adap-org
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The categories of this paper are: acc-phys
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The categories of this paper are: nlin
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The categories of this paper are: q-alg
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The categories of this paper are: econ
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The categories of this paper are: ao-sci
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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: math-ph
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The categories of this paper are: eess