Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A consistent model for \pi N transition distribution amplitudes and
  backward pion electroproduction   The extension of the concept of generalized parton distributions leads to the
introduction of baryon to meson transition distribution amplitudes (TDAs),
non-diagonal matrix elements of the nonlocal three quark operator between a
nucleon and a meson state. We present a general framework for modelling nucleon
to pion ($\pi N$) TDAs. Our main tool is the spectral representation for \pi N
TDAs in terms of quadruple distributions. We propose a factorized Ansatz for
quadruple distributions with input from the soft-pion theorem for \pi N TDAs.
The spectral representation is complemented with a D-term like contribution
from the nucleon exchange in the cross channel. We then study backward pion
electroproduction in the QCD collinear factorization approach in which the
non-perturbative part of the amplitude involves \pi N TDAs. Within our two
component model for \pi N TDAs we update previous leading-twist estimates of
the unpolarized cross section. Finally, we compute the transverse target single
spin asymmetry as a function of skewness. We find it to be sizable in the
valence region and sensitive to the phenomenological input of our \pi N TDA
model.

20
The categories of this paper are: acc-phys
31
The categories of this paper are: ao-sci
10
The categories of this paper are: q-bio
5
The categories of this paper are: gr-qc
23
The categories of this paper are: solv-int
19
The categories of this paper are: eess
4
The categories of this paper are: cond-mat
24
The categories of this paper are: dg-ga
9
The categories of this paper are: nlin
26
The categories of this paper are: bayes-an
14
The categories of this paper are: math-ph
11
The categories of this paper are: hep-lat
28
The categories of this paper are: alg-geom
6
The categories of this paper are: astro-ph
37
The categories of this paper are: supr-con
36
The categories of this paper are: cmp-lg