Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A lattice calculation of the nucleon's spin-dependent structure function
  g_2 revisited   Our previous calculation of the spin-dependent structure function g_2 is
revisited. The interest in this structure function is to a great extent
motivated by the fact that it receives contributions from twist-two as well as
from twist-three operators already in leading order of 1/Q^2 thus offering the
unique possibility of directly assessing higher-twist effects. In our former
calculation the lattice operators were renormalized perturbatively and mixing
with lower-dimensional operators was ignored. However, the twist-three operator
which gives rise to the matrix element d_2 mixes non-perturbatively with an
operator of lower dimension. Taking this effect into account leads to a
considerably smaller value of d_2, which is consistent with the experimental
data.

30
The categories of this paper are: q-alg
19
The categories of this paper are: eess
33
The categories of this paper are: plasm-ph
32
The categories of this paper are: atom-ph
20
The categories of this paper are: acc-phys
25
The categories of this paper are: patt-sol
28
The categories of this paper are: alg-geom
23
The categories of this paper are: solv-int
10
The categories of this paper are: q-bio
8
The categories of this paper are: hep-ex
16
The categories of this paper are: stat
2
The categories of this paper are: math
34
The categories of this paper are: chem-ph
5
The categories of this paper are: gr-qc
3
The categories of this paper are: physics
24
The categories of this paper are: dg-ga