Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Chiral dynamics in the gamma p --> pi^0 eta p and gamma p --> pi^0 K^0
  Sigma^+ reactions   Using a chiral unitary approach for meson-baryon scattering in the
strangeness zero sector, where the $N^*(1535)$ resonance is dynamically
generated, we study the reactions $\gamma p \to \pi^0 \eta p$ and $\gamma p \to
\pi^0 K^0 \Sigma^+$ at photon energies at which the final states are produced
close to threshold. Among several reaction mechanisms, we find the most
important is the excitation of the $\Delta^*(1700)$ state which subsequently
decays into a pseudoscalar meson and a baryon belonging to the $\Delta(1232)$
decuplet. Hence, the reaction provides useful information with which to test
current theories of the dynamical generation of the low-lying $3/2^-$ states.
The first reaction is shown to lead to sizable cross sections and the
$N^*(1535)$ resonance shape is seen clearly in the $\eta p$ invariant mass
distribution. The same dynamical model is shown to lead to much smaller cross
sections at low energies in the second reaction. Predictions are made for cross
sections and invariant mass distributions which can be compared with
forthcoming experiments at ELSA.

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The categories of this paper are: econ
3
The categories of this paper are: physics
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The categories of this paper are: eess
1
The categories of this paper are: cs
37
The categories of this paper are: supr-con
0
The categories of this paper are: hep-ph
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The categories of this paper are: math-ph
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The categories of this paper are: bayes-an
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The categories of this paper are: acc-phys
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The categories of this paper are: cond-mat
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The categories of this paper are: hep-ex
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The categories of this paper are: cmp-lg
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The categories of this paper are: patt-sol
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The categories of this paper are: atom-ph
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The categories of this paper are: chem-ph
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The categories of this paper are: q-alg