Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Constraining right-handed neutrinos   Several models of neutrino masses predict the existence of neutral heavy
leptons. Here, we review current constraints on heavy neutrinos and apply a new
formalism separating new physics from Standard Model. We discuss also the
indirect effect of extra heavy neutrinos in oscillation experiments.

5
The categories of this paper are: gr-qc
35
The categories of this paper are: mtrl-th
27
The categories of this paper are: comp-gas
24
The categories of this paper are: dg-ga
30
The categories of this paper are: q-alg
16
The categories of this paper are: stat
23
The categories of this paper are: solv-int
14
The categories of this paper are: math-ph
3
The categories of this paper are: physics
2
The categories of this paper are: math
37
The categories of this paper are: supr-con
31
The categories of this paper are: ao-sci
19
The categories of this paper are: eess
9
The categories of this paper are: nlin
1
The categories of this paper are: cs
12
The categories of this paper are: nucl-th