Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Theory of Coupled Pion--Trinucleon Systems   We derive the dynamical equations which consistently couple the four--body
($\pi$NNN) system to the underlying three--nucleon system. Our treatment can be
considered the proper generalization of the Afnan--Blankleider equations for
the coupled NN--$\pi$NN system. The resulting connected--kernel equation
resembles in structure the Yakubovskii--Grassberger--Sandhas equation for the
standard four--body problem, but involves 24 chain--labelled components (rather
than the usual 18 ones) and allows for a consistent evaluation of reaction
amplitudes involving $\pi$ absorption/production.

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The categories of this paper are: quant-ph
4
The categories of this paper are: cond-mat
0
The categories of this paper are: hep-ph
35
The categories of this paper are: mtrl-th
17
The categories of this paper are: q-fin
24
The categories of this paper are: dg-ga
27
The categories of this paper are: comp-gas
18
The categories of this paper are: econ
23
The categories of this paper are: solv-int
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The categories of this paper are: acc-phys
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The categories of this paper are: nlin
32
The categories of this paper are: atom-ph
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The categories of this paper are: q-alg
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The categories of this paper are: stat
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The categories of this paper are: chao-dyn
3
The categories of this paper are: physics