Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Spin-flavor structure of chiral-odd GPDs in the large-N_c limit   We study the spin-flavor structure of the nucleon's chiral-odd generalized
parton distributions (transversity GPDs) in the large-N_c limit of QCD. In
contrast to the chiral-even case, only three combinations of the four
chiral-odd GPDs are non-zero in the leading order of the 1/N_c expansion:
E_T-bar = E_T + 2 H_T-tilde, H_T and E_T-tilde. The degeneracy is explained by
the absence of spin-orbit interactions correlating the transverse momentum
transfer with the transverse quark spin. It can also be deduced from the
natural N_c-scaling of the quark-nucleon helicity amplitudes associated with
the GPDs. In the GPD E_T-bar the flavor-singlet component u + d is leading in
the 1/N_c expansion, while in H_T and E_T-tilde it is the flavor-nonsinglet
components u - d. The large-N_c relations are consistent with the spin-flavor
structure extracted from hard exclusive pi0 and eta electroproduction data, if
it is assumed that the processes are mediated by twist-3 amplitudes involving
the chiral-odd GPDs and the chiral-odd pseudoscalar meson distribution
amplitudes.

13
The categories of this paper are: quant-ph
5
The categories of this paper are: gr-qc
30
The categories of this paper are: q-alg
23
The categories of this paper are: solv-int
21
The categories of this paper are: adap-org
8
The categories of this paper are: hep-ex
11
The categories of this paper are: hep-lat
1
The categories of this paper are: cs
37
The categories of this paper are: supr-con
16
The categories of this paper are: stat
27
The categories of this paper are: comp-gas
15
The categories of this paper are: nucl-ex
32
The categories of this paper are: atom-ph
29
The categories of this paper are: funct-an
19
The categories of this paper are: eess
17
The categories of this paper are: q-fin