Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Astropulse: A Search for Microsecond Transient Radio Signals Using
  Distributed Computing. I. Methodology   We are performing a transient, microsecond timescale radio sky survey, called
"Astropulse," using the Arecibo telescope. Astropulse searches for brief (0.4
{\mu}s to 204.8 {\mu}s), wideband (relative to its 2.5 MHz bandwidth) radio
pulses centered at 1,420 MHz. Astropulse is a commensal (piggyback) survey, and
scans the sky between declinations of -1.33 and 38.03 degrees. We obtained
1,540 hours of data in each of 7 beams of the ALFA receiver, with 2
polarizations per beam. Examination of timescales on the order of a few
microseconds is possible because we used coherent dedispersion. The more usual
technique, incoherent dedispersion, cannot resolve signals below a minimum
timescale. However, coherent dedispersion requires more intensive computation
than incoherent dedispersion. The required processing power was provided by
BOINC, the Berkeley Open Infrastructure for Network Computing.

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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: eess
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The categories of this paper are: atom-ph
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The categories of this paper are: physics
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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-ph
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The categories of this paper are: cond-mat
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The categories of this paper are: adap-org
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The categories of this paper are: q-bio
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The categories of this paper are: chao-dyn
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The categories of this paper are: ao-sci
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The categories of this paper are: q-fin
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The categories of this paper are: patt-sol
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The categories of this paper are: acc-phys