Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Neutrino masses and Z' physics   The characteristic scale of neutral current, provided by an extension of
Standard Model with a local group over the right-handed fermions, determines
the smallness of neutrino masses of Dirac kind. The experimental observation of
neutrino oscillations imposes the stringent limit on the $Z^\prime$ physics
appearance at low energies.

30
The categories of this paper are: q-alg
10
The categories of this paper are: q-bio
8
The categories of this paper are: hep-ex
9
The categories of this paper are: nlin
5
The categories of this paper are: gr-qc
3
The categories of this paper are: physics
21
The categories of this paper are: adap-org
24
The categories of this paper are: dg-ga
18
The categories of this paper are: econ
28
The categories of this paper are: alg-geom
6
The categories of this paper are: astro-ph
36
The categories of this paper are: cmp-lg
29
The categories of this paper are: funct-an
34
The categories of this paper are: chem-ph
37
The categories of this paper are: supr-con
7
The categories of this paper are: hep-th