Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Transverse Charge Densities   Electromagnetic form factors have long been used to probe the underlying
charge and magnetization densities of hadrons and nuclei. Traditional
three-dimensional Fourier transform methods are not rigorously applicable for
systems with constituents that move relativistically. The use of the transverse
charge density is a new, rigorously defined way to analyze electromagnetic form
factors of hadrons.This review is concerned with the following issues: what is
a transverse charge density; how is one extracted one from elastic scattering
data; the existing results; what is the relationship with other observable
quantities; and, future prospects.

23
The categories of this paper are: solv-int
35
The categories of this paper are: mtrl-th
11
The categories of this paper are: hep-lat
33
The categories of this paper are: plasm-ph
16
The categories of this paper are: stat
34
The categories of this paper are: chem-ph
2
The categories of this paper are: math
5
The categories of this paper are: gr-qc
22
The categories of this paper are: chao-dyn
29
The categories of this paper are: funct-an
13
The categories of this paper are: quant-ph
7
The categories of this paper are: hep-th
37
The categories of this paper are: supr-con
31
The categories of this paper are: ao-sci
26
The categories of this paper are: bayes-an
32
The categories of this paper are: atom-ph