Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The low-energy constants of the pion-nucleon system   Recent analyses of low-energy pion-nucleon experimental data have provided
clear evidence for the violation of the isospin symmetry of the strong
interaction. In the present work, it is shown that the single-charge-exchange
reaction is the culprit for the effect. Given the present experimental
uncertainties, no evidence for isospin breaking was found in the two
elastic-scattering processes for pion laboratory kinetic energies between 20
and 100 MeV. In agreement with most of the recent determinations, the value for
the charged-pion coupling constant, extracted herein, is `small'. The energy
dependence of the s- and p-wave hadronic phase shifts, obtained from low-energy
elastic-scattering data exclusively, as well as their values in tabular form
(including meaningful uncertainties), are provided. Discrepancies with two
`standard' phase-shift solutions in the s-wave part of the interaction are
seen; small differences may be observed in three of the p-wave channels.

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The categories of this paper are: atom-ph
27
The categories of this paper are: comp-gas
14
The categories of this paper are: math-ph
6
The categories of this paper are: astro-ph
24
The categories of this paper are: dg-ga
3
The categories of this paper are: physics
19
The categories of this paper are: eess
7
The categories of this paper are: hep-th
30
The categories of this paper are: q-alg
18
The categories of this paper are: econ
9
The categories of this paper are: nlin
29
The categories of this paper are: funct-an
36
The categories of this paper are: cmp-lg
26
The categories of this paper are: bayes-an
31
The categories of this paper are: ao-sci
37
The categories of this paper are: supr-con