Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Measurement of the Absolute Differential Cross Section for np Elastic
  Scattering at 194 MeV   A tagged medium-energy neutron beam has been used in a precise measurement of
the absolute differential cross section for np back-scattering. The results
resolve significant discrepancies within the np database concerning the angular
dependence in this regime. The experiment has determined the absolute
normalization with 1.5% uncertainty, suitable to verify constraints of
supposedly comparable precision that arise from the rest of the database in
partial wave analyses. The analysis procedures, especially those associated
with evaluation of systematic errors in the experiment, are described in detail
so that systematic uncertainties may be included in a reasonable way in
subsequent partial wave analysis fits incorporating the present results.

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The categories of this paper are: patt-sol
34
The categories of this paper are: chem-ph
10
The categories of this paper are: q-bio
32
The categories of this paper are: atom-ph
7
The categories of this paper are: hep-th
33
The categories of this paper are: plasm-ph
4
The categories of this paper are: cond-mat
28
The categories of this paper are: alg-geom
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The categories of this paper are: comp-gas
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The categories of this paper are: nucl-th
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The categories of this paper are: physics
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The categories of this paper are: q-fin
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The categories of this paper are: funct-an
0
The categories of this paper are: hep-ph
30
The categories of this paper are: q-alg
14
The categories of this paper are: math-ph