Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Pi and PiPi Decays of Excited D Mesons   The $\pi$ and $\pi\pi$ decay widths of the excited charm mesons are
calculated using a Hamiltonian model within the framework of the covariant
Blankenbecler-Sugar equation. The pion-light constituent quark coupling is
described by the chiral pseudovector Lagrangian.

36
The categories of this paper are: cmp-lg
7
The categories of this paper are: hep-th
33
The categories of this paper are: plasm-ph
23
The categories of this paper are: solv-int
18
The categories of this paper are: econ
37
The categories of this paper are: supr-con
32
The categories of this paper are: atom-ph
12
The categories of this paper are: nucl-th
26
The categories of this paper are: bayes-an
11
The categories of this paper are: hep-lat
3
The categories of this paper are: physics
20
The categories of this paper are: acc-phys
16
The categories of this paper are: stat
27
The categories of this paper are: comp-gas
1
The categories of this paper are: cs
9
The categories of this paper are: nlin