Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Experimental investigation of coherent Smith-Purcell radiation from a
  "flat" grating   Using the pre-bunched electron beam of 5-MeV linear accelerator the coherent
Smith-Purcell radiation (CSPR) from a flat periodic target (made of conductive
layers separated by dielectric gaps) in millimeter wavelength region has been
investigated. The angular distribution of this radiation was measured with a
narrow-band detector and experimental data agree with our theoretical
calculations for similar kind of targets. Such properties of Smith-Purcell
radiation as strong dependence of radiation wavelength on the observation angle
overlapping with coherent radiation effect may be used for a noninvasive bunch
length measurement. The possibility of using the room temperature detectors for
single bunch measurements is demonstrated.

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The categories of this paper are: comp-gas
14
The categories of this paper are: math-ph
26
The categories of this paper are: bayes-an
25
The categories of this paper are: patt-sol
11
The categories of this paper are: hep-lat
32
The categories of this paper are: atom-ph
20
The categories of this paper are: acc-phys
4
The categories of this paper are: cond-mat
1
The categories of this paper are: cs
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The categories of this paper are: solv-int
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The categories of this paper are: plasm-ph
10
The categories of this paper are: q-bio
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The categories of this paper are: cmp-lg
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The categories of this paper are: q-alg
13
The categories of this paper are: quant-ph
7
The categories of this paper are: hep-th