Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Solvable model for pair excitation in trapped Boson gas at zero
  temperature   In Bose-Einstein condensation, a macroscopically large number of particles
occupy the same single-particle quantum state. Our goal is to study
time-dependent aspects of particle excitations to states other than the
single-particle macroscopic state in trapped dilute atomic gases. We adopt the
view that atoms are excited in pairs so that their scattering from the
single-particle state to vector positions x and y at time t is described by the
pair-excitation function, K0(x,y,t). We solve a nonlocal equation for K0 under
a slowly varying external potential by assuming that the wave function of the
macroscopic state satisfies a time-independent nonlinear Schroedinger equation.
For zero initial excitation (K0=0 at t=0) and sufficiently large t, we evaluate
asymptotically K0 in terms of the one-variable Lommel function for any distance
|x-y|.

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The categories of this paper are: nucl-th
32
The categories of this paper are: atom-ph
5
The categories of this paper are: gr-qc
31
The categories of this paper are: ao-sci
22
The categories of this paper are: chao-dyn
3
The categories of this paper are: physics
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The categories of this paper are: stat
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The categories of this paper are: dg-ga
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The categories of this paper are: cmp-lg
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The categories of this paper are: bayes-an
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The categories of this paper are: comp-gas
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The categories of this paper are: nlin
1
The categories of this paper are: cs
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The categories of this paper are: adap-org
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The categories of this paper are: alg-geom
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The categories of this paper are: eess