Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Neutron size from high energy scattering data   Alvarado, Aranda, and Bonilla propose a sub-GeV U(1)R gauge boson model to
explain the proton charge radius discrepancy. Their model assumes opposite sign
U(1)R charge assignments for up and down quarks in the nucleon. I point out
that might cause a difference between neutron and proton mass radii that
contradicts existing p-p and n-p scattering data. Using existing neutron and
proton scattering data I show that the neutron and proton mass radii are equal
within about 2%. This constitutes a challenge to models that attempt to explain
the discrepancy by modifying the quark couplings.

22
The categories of this paper are: chao-dyn
7
The categories of this paper are: hep-th
5
The categories of this paper are: gr-qc
17
The categories of this paper are: q-fin
27
The categories of this paper are: comp-gas
1
The categories of this paper are: cs
2
The categories of this paper are: math
18
The categories of this paper are: econ
33
The categories of this paper are: plasm-ph
24
The categories of this paper are: dg-ga
3
The categories of this paper are: physics
34
The categories of this paper are: chem-ph
37
The categories of this paper are: supr-con
31
The categories of this paper are: ao-sci
32
The categories of this paper are: atom-ph
14
The categories of this paper are: math-ph