Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Integral equations for the four-body problem   We consider the four-boson and 3+1 fermionic problems with a model
Hamiltonian which encapsulates the mechanism of the Feshbach resonance
involving the coherent coupling of two atoms in the open channel and a molecule
in the closed channel. The model includes also the pair-wise direct interaction
between atoms in the open channel and in the bosonic case, the direct
molecule-molecule interaction in the closed channel. Interactions are modeled
by separable potentials which makes it possible to reduce the four-body problem
to the study of a single integral equation. We take advantage of the rotational
symmetry and parity invariance of the Hamiltonian to reduce the general
eigenvalue equation in each angular momentum sector to an integral equation for
functions of three real variables only. A first application of this formalism
in the zero-range limit is given elsewhere [Y. Castin, C. Mora, L. Pricoupenko,
Phys. Rev. Lett. 105, 223201 (2010)].

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The categories of this paper are: atom-ph
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The categories of this paper are: hep-th
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The categories of this paper are: supr-con
5
The categories of this paper are: gr-qc
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The categories of this paper are: dg-ga
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The categories of this paper are: math-ph
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The categories of this paper are: patt-sol
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The categories of this paper are: cmp-lg
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The categories of this paper are: math
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The categories of this paper are: hep-ex
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The categories of this paper are: comp-gas
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The categories of this paper are: nucl-ex
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The categories of this paper are: cs
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The categories of this paper are: hep-lat
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The categories of this paper are: bayes-an
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The categories of this paper are: econ