Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Azimuthal asymmetries at CLAS: Extraction of e^a(x) and prediction of
  A_{UL}   First information on the chirally odd twist-3 proton distribution function
e(x) is extracted from the azimuthal asymmetry, A_{LU}, in the
electro-production of pions from deeply inelastic scattering of longitudinally
polarized electrons off unpolarized protons, which has been recently measured
by CLAS collaboration. Furthermore parameter-free predictions are made for
azimuthal asymmetries, A_{UL}, from scattering of an unpolarized beam on a
polarized proton target for CLAS kinematics.

8
The categories of this paper are: hep-ex
11
The categories of this paper are: hep-lat
26
The categories of this paper are: bayes-an
6
The categories of this paper are: astro-ph
7
The categories of this paper are: hep-th
13
The categories of this paper are: quant-ph
14
The categories of this paper are: math-ph
2
The categories of this paper are: math
22
The categories of this paper are: chao-dyn
31
The categories of this paper are: ao-sci
20
The categories of this paper are: acc-phys
10
The categories of this paper are: q-bio
36
The categories of this paper are: cmp-lg
24
The categories of this paper are: dg-ga
37
The categories of this paper are: supr-con
34
The categories of this paper are: chem-ph