Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Hierarchical Quark and Lepton Masses with Sequential U(1) Gauge Symmetry   Instead of right-handed neutrino singlets, the standard model is extended to
include lepton triplets $(\Sigma^+, \Sigma^0, \Sigma^-)$. Each quark and lepton
family may now transform under an anomaly-free $U(1)_X$ gauge symmetry, known
already for many years. A new sequential application is presented, using just
the one Higgs doublet of the standard model, together with two $U(1)_X$ Higgs
singlets. The resulting structure has hierarchical quark and lepton masses, as
well as a viable seesaw neutrino mass matrix.

27
The categories of this paper are: comp-gas
6
The categories of this paper are: astro-ph
2
The categories of this paper are: math
20
The categories of this paper are: acc-phys
14
The categories of this paper are: math-ph
26
The categories of this paper are: bayes-an
35
The categories of this paper are: mtrl-th
16
The categories of this paper are: stat
29
The categories of this paper are: funct-an
34
The categories of this paper are: chem-ph
28
The categories of this paper are: alg-geom
23
The categories of this paper are: solv-int
3
The categories of this paper are: physics
1
The categories of this paper are: cs
30
The categories of this paper are: q-alg
11
The categories of this paper are: hep-lat