Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On the spectral functions of scalar mesons   In this work we study the spectral functions of scalar mesons in one- and
two-channel cases. When the propagators satisfy the K\"allen-Lehman
representation a normalized spectral function is obtained, allowing to take
into account finite-width effects in the evaluation of decay rates. In the
one-channel case, suitable to the light sigma and k mesons, the spectral
function can deviate consistently from a Breit-Wigner shape. In the two-channel
case with one subthreshold channel the evaluated spectral function is well
approximated by a Flatte' distribution; when applying the study to the a_0(980)
and f_0(980) mesons the tree-level forbidden KK decay is analysed.

7
The categories of this paper are: hep-th
24
The categories of this paper are: dg-ga
32
The categories of this paper are: atom-ph
4
The categories of this paper are: cond-mat
22
The categories of this paper are: chao-dyn
30
The categories of this paper are: q-alg
31
The categories of this paper are: ao-sci
35
The categories of this paper are: mtrl-th
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
19
The categories of this paper are: eess
33
The categories of this paper are: plasm-ph
17
The categories of this paper are: q-fin
37
The categories of this paper are: supr-con
25
The categories of this paper are: patt-sol