Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Scattering amplitudes for e^+e^- --> 3 jets at next-to-next-to-leading
  order QCD   We present the calculation of the fermionic contribution to the QCD two-loop
amplitude for e^+e^- --> q qbar g.

22
The categories of this paper are: chao-dyn
35
The categories of this paper are: mtrl-th
3
The categories of this paper are: physics
33
The categories of this paper are: plasm-ph
17
The categories of this paper are: q-fin
21
The categories of this paper are: adap-org
5
The categories of this paper are: gr-qc
23
The categories of this paper are: solv-int
8
The categories of this paper are: hep-ex
18
The categories of this paper are: econ
13
The categories of this paper are: quant-ph
10
The categories of this paper are: q-bio
27
The categories of this paper are: comp-gas
28
The categories of this paper are: alg-geom
29
The categories of this paper are: funct-an
9
The categories of this paper are: nlin