Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Vector form factor of the pion : A model-independent approach   We study a model-independent parameterization of the vector pion form factor
that arises from the constraints of analyticity and unitarity. Our description
should be suitable up to s^(1/2) ~ 1.2 GeV and allows a model-independent
determination of the mass of the rho(770) resonance. We analyse the
experimental data on tau^- -> pion^- pion^0 nu_tau and e^+ e^- -> pion^+ pion^-
in this framework, and its consequences on the low-energy observables worked
out by chiral perturbation theory. An evaluation of the two pion contribution
to the anomalous magnetic moment of the muon, a_{mu}, and to the fine structure
constant, alpha(M_Z^2), is also performed.

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The categories of this paper are: astro-ph
18
The categories of this paper are: econ
13
The categories of this paper are: quant-ph
33
The categories of this paper are: plasm-ph
9
The categories of this paper are: nlin
28
The categories of this paper are: alg-geom
32
The categories of this paper are: atom-ph
25
The categories of this paper are: patt-sol
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The categories of this paper are: q-fin
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The categories of this paper are: acc-phys
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The categories of this paper are: cond-mat
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The categories of this paper are: solv-int
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The categories of this paper are: chem-ph
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The categories of this paper are: hep-lat
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The categories of this paper are: math-ph
1
The categories of this paper are: cs