Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Measurement of the proton electric to magnetic form factor ratio from
  \vec ^1H(\vec e, e'p)   We report the first precision measurement of the proton electric to magnetic
form factor ratio from spin-dependent elastic scattering of longitudinally
polarized electrons from a polarized hydrogen internal gas target. The
measurement was performed at the MIT-Bates South Hall Ring over a range of
four-momentum transfer squared $Q^2$ from 0.15 to 0.65 (GeV/c)$^2$.
Significantly improved results on the proton electric and magnetic form factors
are obtained in combination with previous cross-section data on elastic
electron-proton scattering in the same $Q^2$ region.

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The categories of this paper are: stat
26
The categories of this paper are: bayes-an
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The categories of this paper are: hep-th
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The categories of this paper are: hep-lat
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The categories of this paper are: astro-ph
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The categories of this paper are: adap-org
10
The categories of this paper are: q-bio
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The categories of this paper are: patt-sol
33
The categories of this paper are: plasm-ph
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The categories of this paper are: mtrl-th
32
The categories of this paper are: atom-ph
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The categories of this paper are: dg-ga
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The categories of this paper are: alg-geom
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The categories of this paper are: eess
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The categories of this paper are: math-ph
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The categories of this paper are: q-fin