Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Superradiance from BEC vortices: a numerical study   The scattering of sound wave perturbations from vortex excitations of
Bose-Einstein condensates(BEC) is investigated by numerical integration of the
associated Klein-Gordon equation. It is found that, at sufficiently high
angular speeds, sound wave-packets can extract a sizeable fraction of the
vortex energy through a mechanism of superradiant scattering. It is conjectured
that this superradiant regime may be detectable in BEC experiments.

37
The categories of this paper are: supr-con
17
The categories of this paper are: q-fin
27
The categories of this paper are: comp-gas
34
The categories of this paper are: chem-ph
12
The categories of this paper are: nucl-th
0
The categories of this paper are: hep-ph
15
The categories of this paper are: nucl-ex
4
The categories of this paper are: cond-mat
3
The categories of this paper are: physics
26
The categories of this paper are: bayes-an
14
The categories of this paper are: math-ph
2
The categories of this paper are: math
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The categories of this paper are: ao-sci
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The categories of this paper are: adap-org
8
The categories of this paper are: hep-ex
33
The categories of this paper are: plasm-ph