Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Chiral unitary approach to hadron spectroscopy   The s-wave meson-baryon interaction in the $S = -1$, $S= 0$ and $S= -2$
sectors is studied by means of coupled channels, using the lowest-order chiral
Lagrangian and the N/D method or equivalently the Bethe-Salpeter equation to
implement unitarity.
  This chiral approach leads to the dynamical generation of the $\Lambda
(1405)$, $\Lambda(1670)$ and $\Sigma(1620)$ states for $S = -1$, the
$N^*(1535)$ for $S= 0$ and the $\Xi(1620)$ for $S= -2$. We look for poles in
the complex plane and extract the couplings of the resonances to the different
final states. This allows identifying the $\Lambda (1405)$ and the
$\Lambda(1670)$ resonances with $\bar{K}N$ and $K\Xi$ quasibound states,
respectively. Our results are found to be incompatible with the measured
properties of the $\Xi(1690)$ resonance, thus ruling this state out as the
remaining member of this octet of dynamically generated resonances. We
therefore assign $1/2^-$ for the spin and parity of the $\Xi(1620)$ resonance
as the $S=-2$ member of the lowest-lying $1/2^-$ octet.

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The categories of this paper are: eess
32
The categories of this paper are: atom-ph
15
The categories of this paper are: nucl-ex
9
The categories of this paper are: nlin
5
The categories of this paper are: gr-qc
36
The categories of this paper are: cmp-lg
25
The categories of this paper are: patt-sol
8
The categories of this paper are: hep-ex
3
The categories of this paper are: physics
22
The categories of this paper are: chao-dyn
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The categories of this paper are: quant-ph
21
The categories of this paper are: adap-org
4
The categories of this paper are: cond-mat
37
The categories of this paper are: supr-con
16
The categories of this paper are: stat
27
The categories of this paper are: comp-gas