Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Gamma Ray Large Area Space Telescope (GLAST) Balloon Flight Data
  Handling Overview   The GLAST Balloon Flight Engineering Model (BFEM) represents one of 16 towers
that constitute the Large Area Telescope (LAT), a high-energy (>20 MeV)
gamma-ray pair-production telescope being built by an international partnership
of astrophysicists and particle physicists for a satellite launch in 2006. The
prototype tower consists of a Pb/Si pair-conversion tracker (TKR), a CsI
hodoscopic calorimeter (CAL), an anti-coincidence detector (ACD) and an
autonomous data acquisition system (DAQ). The self-triggering capabilities and
performance of the detector elements have been previously characterized using
positron, photon and hadron beams. External target scintillators were placed
above the instrument to act as sources of hadronic showers. This paper provides
a comprehensive description of the BFEM data-reduction process, from receipt of
the flight data from telemetry through event reconstruction and background
rejection cuts. The goals of the ground analysis presented here are to verify
the functioning of the instrument and to validate the reconstruction software
and the background-rejection scheme.

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The categories of this paper are: plasm-ph
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The categories of this paper are: quant-ph
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The categories of this paper are: eess
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The categories of this paper are: bayes-an
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The categories of this paper are: econ
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The categories of this paper are: hep-lat
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The categories of this paper are: chao-dyn
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The categories of this paper are: nlin
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The categories of this paper are: supr-con
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The categories of this paper are: q-fin
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The categories of this paper are: chem-ph
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The categories of this paper are: hep-th
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The categories of this paper are: comp-gas
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The categories of this paper are: atom-ph
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The categories of this paper are: mtrl-th
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The categories of this paper are: nucl-th