Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The effect of the in-medium $\Theta^+$ pentaquark on the kaon optical
  potential   The kaon nuclear optical potential is studied including the effect of the
$\Theta^+$ pentaquark. The one-nucleon contribution is obtained using an
extension of the J\"ulich meson-exchange potential as bare kaon-nucleon
interaction. Significant differences between a fully self-consistent
calculation and the usually employed low-density $T\rho$ approach are observed.
The influence of the one-nucleon absorption process, $K N \to \Theta^+$, on the
kaon optical potential is negligible due to the small width of the pentaquark.
In contrast, the two-nucleon mechanism, $K N N \to \Theta^+ N$, estimated from
the coupling of the pentaquark to a two-meson cloud, provides the required
amount of additional kaon absorption to reconcile with data the systematically
low $K^+$-nucleus reaction cross sections found by the theoretical models.

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The categories of this paper are: quant-ph
7
The categories of this paper are: hep-th
33
The categories of this paper are: plasm-ph
14
The categories of this paper are: math-ph
22
The categories of this paper are: chao-dyn
23
The categories of this paper are: solv-int
2
The categories of this paper are: math
32
The categories of this paper are: atom-ph
36
The categories of this paper are: cmp-lg
8
The categories of this paper are: hep-ex
4
The categories of this paper are: cond-mat
9
The categories of this paper are: nlin
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The categories of this paper are: hep-lat
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The categories of this paper are: alg-geom
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The categories of this paper are: funct-an
10
The categories of this paper are: q-bio