Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Instanton Effects in the Decay of Scalar Mesons   We show that instanton effects may play a crucial role in the decay of scalar
mesons into two pseudoscalars. Particularly the branching ratios of two meson
decays of the $f_0(1500)$, which is considered as a glue-ball candidate, are
then compatible with an ordinary $q \bar{q}$-structure of this resonance and a
small positive SU(3) mixing angle, close to a result recently calculated with
the same instanton-induced force.

23
The categories of this paper are: solv-int
13
The categories of this paper are: quant-ph
3
The categories of this paper are: physics
20
The categories of this paper are: acc-phys
1
The categories of this paper are: cs
24
The categories of this paper are: dg-ga
33
The categories of this paper are: plasm-ph
30
The categories of this paper are: q-alg
12
The categories of this paper are: nucl-th
31
The categories of this paper are: ao-sci
14
The categories of this paper are: math-ph
29
The categories of this paper are: funct-an
26
The categories of this paper are: bayes-an
16
The categories of this paper are: stat
15
The categories of this paper are: nucl-ex
17
The categories of this paper are: q-fin