Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Electromagnetic properties of the neutrinos and the pion radiative decay   We investigate the implications of neutrino electromagnetic dipole moments
for the radiative decay $\pi \rightarrow e \nu \gamma$. We show that the
dominant new effect comes from the interference between the amplitude of the
process with the photon emitted by the neutrino and the structure dependent
standard amplitude. Such interference takes place only if the massive neutrino
is a Majorana fermion. Moreover, since electric and magnetic dipole moments
give rise to contributions with opposite signs, future experiments might be
able to distinguish between them.

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The categories of this paper are: hep-lat
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The categories of this paper are: hep-th
4
The categories of this paper are: cond-mat
27
The categories of this paper are: comp-gas
8
The categories of this paper are: hep-ex
33
The categories of this paper are: plasm-ph
34
The categories of this paper are: chem-ph
28
The categories of this paper are: alg-geom
26
The categories of this paper are: bayes-an
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The categories of this paper are: econ
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The categories of this paper are: q-fin
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The categories of this paper are: stat
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The categories of this paper are: astro-ph
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The categories of this paper are: gr-qc
2
The categories of this paper are: math
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The categories of this paper are: nucl-th