Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Pion light-front wave function, parton distribution and the
  electromagnetic form factor   We derive the lowest-order $q\bar q$ valence light-front wave function for
the pion with Lz=0 and |Lz|=1, which reproduces its valence parton distribution
and the electromagnetic form factor consistent with data.

3
The categories of this paper are: physics
16
The categories of this paper are: stat
23
The categories of this paper are: solv-int
11
The categories of this paper are: hep-lat
14
The categories of this paper are: math-ph
20
The categories of this paper are: acc-phys
29
The categories of this paper are: funct-an
7
The categories of this paper are: hep-th
1
The categories of this paper are: cs
19
The categories of this paper are: eess
6
The categories of this paper are: astro-ph
35
The categories of this paper are: mtrl-th
32
The categories of this paper are: atom-ph
25
The categories of this paper are: patt-sol
34
The categories of this paper are: chem-ph
10
The categories of this paper are: q-bio