Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Nucleon Form Factors in the Space- and Timelike Regions   Dispersion relations provide a powerful tool to describe the electromagnetic
form factors of the nucleon both in the spacelike and timelike regions with
constraints from unitarity and perturbative QCD. We give a brief introduction
into dispersion theory for nucleon form factors and present results from a
recent form factor analysis. Particular emphasis is given to the form factors
in the timelike region. Furthermore, some recent results for the spacelike form
factors at low momentum transfer from a ChPT calculation by Kubis and Meissner
are discussed.

19
The categories of this paper are: eess
8
The categories of this paper are: hep-ex
36
The categories of this paper are: cmp-lg
25
The categories of this paper are: patt-sol
16
The categories of this paper are: stat
34
The categories of this paper are: chem-ph
7
The categories of this paper are: hep-th
26
The categories of this paper are: bayes-an
13
The categories of this paper are: quant-ph
29
The categories of this paper are: funct-an
2
The categories of this paper are: math
33
The categories of this paper are: plasm-ph
32
The categories of this paper are: atom-ph
21
The categories of this paper are: adap-org
31
The categories of this paper are: ao-sci
1
The categories of this paper are: cs