Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Lepton Number Violation in TeV Scale See-Saw Extensions of the Standard
  Model   The low-energy neutrino physics constraints on the TeV scale type I see-saw
scenarios of neutrino mass generation are revisited. It is shown that lepton
charge (L) violation, associated to the production and decays of heavy Majorana
neutrinos N_{j} having masses in the range of M_j \sim (100 \div 1000) GeV and
present in such scenarios, is hardly to be observed at ongoing and future
particle accelerator experiments, LHC included, because of very strong
constraints on the parameters and couplings responsible for the corresponding
|\Delta L| = 2 processes. If the heavy Majorana neutrinos N_j are observed and
they are associated only with the type I mechanism, they will behave
effectively like pseudo-Dirac fermions. Conversely, the observation of effects
proving the Majorana nature of N_j would imply that these heavy neutrinos have
additional relatively strong couplings to the Standard Model particles or that
light neutrino masses compatible with the observations are generated by a
mechanism other than see-saw (e.g., radiatively at one or two loop level) in
which the heavy Majorana neutrinos N_j are nevertheless involved.

25
The categories of this paper are: patt-sol
29
The categories of this paper are: funct-an
30
The categories of this paper are: q-alg
5
The categories of this paper are: gr-qc
1
The categories of this paper are: cs
4
The categories of this paper are: cond-mat
36
The categories of this paper are: cmp-lg
10
The categories of this paper are: q-bio
28
The categories of this paper are: alg-geom
15
The categories of this paper are: nucl-ex
37
The categories of this paper are: supr-con
2
The categories of this paper are: math
33
The categories of this paper are: plasm-ph
6
The categories of this paper are: astro-ph
7
The categories of this paper are: hep-th
19
The categories of this paper are: eess