Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Toy model for two chiral nonets   Motivated by the possibility that nonets of scalar mesons might be described
as mixtures of "two quark" and "four quark" components, we further study a toy
model in which corresponding chiral nonets (containing also the pseudoscalar
partners) interact with each other. Although the "two quark" and "four quark"
chiral fields transform identically under SU(3)$_L \times$ SU(3)$_R$
transformations they transform differently under the U(1)$_A$ transformation
which essentially counts total (quark + antiquark) content of the mesons. To
implement this we formulate an effective Lagrangian which mocks up the U(1)$_A$
behavior of the underlying QCD. We derive generating equations which yield Ward
identity type relations based only on the assumed symmetry structure. This is
applied to the mass spectrum of the low lying pseudoscalars and scalars. as
well as their "excitations". Assuming isotopic spin invariance, it is possible
to disentangle the amount of"two quark" vs."four quark" content in the
pseudoscalar $\pi, K ,\eta$ type states and in the scalar $\kappa$ type states.
It is found that a small "four quark" content in the lightest pseudoscalars is
consistent with a large "four quark" content in the lightest of the scalar
$\kappa$ mesons. The present toy model also allows one to easily estimate the
strength of a "four quark" vacuum condensate. There seems to be a rich and
interesting structure.

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The categories of this paper are: mtrl-th
22
The categories of this paper are: chao-dyn
16
The categories of this paper are: stat
12
The categories of this paper are: nucl-th
14
The categories of this paper are: math-ph
5
The categories of this paper are: gr-qc
20
The categories of this paper are: acc-phys
2
The categories of this paper are: math
15
The categories of this paper are: nucl-ex
6
The categories of this paper are: astro-ph
1
The categories of this paper are: cs
34
The categories of this paper are: chem-ph
7
The categories of this paper are: hep-th
21
The categories of this paper are: adap-org
37
The categories of this paper are: supr-con
3
The categories of this paper are: physics