Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Nonforward Parton Distributions   Applications of perturbative QCD to deeply virtual Compton scattering and
hard exclusive electroproduction processes require a generalization of usual
parton distributions for the case when long-distance information is accumulated
in nonforward matrix elements <p'|O|p> of quark and gluon light-cone operators.
We describe two types of nonperturbative functions parametrizing such matrix
elements: double distributions F(x,y;t) and nonforward distribution functions
F_\zeta (X;t), discuss their spectral properties, evolution equations which
they satisfy, basic uses and general aspects of factorization for hard
exclusive processes.

22
The categories of this paper are: chao-dyn
33
The categories of this paper are: plasm-ph
37
The categories of this paper are: supr-con
28
The categories of this paper are: alg-geom
5
The categories of this paper are: gr-qc
1
The categories of this paper are: cs
13
The categories of this paper are: quant-ph
29
The categories of this paper are: funct-an
34
The categories of this paper are: chem-ph
23
The categories of this paper are: solv-int
32
The categories of this paper are: atom-ph
12
The categories of this paper are: nucl-th
3
The categories of this paper are: physics
36
The categories of this paper are: cmp-lg
6
The categories of this paper are: astro-ph
24
The categories of this paper are: dg-ga