Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Lepton Flavor and Number Conservation, and Physics Beyond the Standard
  Model   The physics responsible for neutrino masses and lepton mixing remains
unknown. More experimental data are needed to constrain and guide possible
generalizations of the standard model of particle physics, and reveal the
mechanism behind nonzero neutrino masses. Here, the physics associated with
searches for the violation of lepton-flavor conservation in charged-lepton
processes and the violation of lepton-number conservation in nuclear physics
processes is summarized. In the first part, several aspects of charged-lepton
flavor violation are discussed, especially its sensitivity to new particles and
interactions beyond the standard model of particle physics. The discussion
concentrates mostly on rare processes involving muons and electrons. In the
second part, the status of the conservation of total lepton number is
discussed. The discussion here concentrates on current and future probes of
this apparent law of Nature via searches for neutrinoless double beta decay,
which is also the most sensitive probe of the potential Majorana nature of
neutrinos.

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The categories of this paper are: physics
18
The categories of this paper are: econ
23
The categories of this paper are: solv-int
30
The categories of this paper are: q-alg
20
The categories of this paper are: acc-phys
16
The categories of this paper are: stat
14
The categories of this paper are: math-ph
27
The categories of this paper are: comp-gas
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The categories of this paper are: hep-th
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The categories of this paper are: gr-qc
36
The categories of this paper are: cmp-lg
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The categories of this paper are: cond-mat
32
The categories of this paper are: atom-ph
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The categories of this paper are: q-bio
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The categories of this paper are: funct-an
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The categories of this paper are: q-fin