Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: QED radiative corrections to the decay pi^0 to e^+e^-   We reconsider QED radiative corrections (RC) to the $\pi^{0}\to e^{+}e^{-}$
decay width. One kind of RC investigated earlier has a renormalization group
origin and can be associated with the final state interaction of electron and
positron. It determines the distribution of lepton pair invariant masses in the
whole kinematic region. The other type of RC has a double-logarithmic character
and is related to almost on-mass-shell behavior of the lepton form factors. The
total effect of RC for the $\pi^{0}\to e^{+}e^{-}$ decay is estimated to be
3.2% and for the decay $\eta \to e^{+}e^{-}$ is 4.3%.

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The categories of this paper are: math
1
The categories of this paper are: cs
24
The categories of this paper are: dg-ga
36
The categories of this paper are: cmp-lg
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The categories of this paper are: comp-gas
10
The categories of this paper are: q-bio
9
The categories of this paper are: nlin
25
The categories of this paper are: patt-sol
13
The categories of this paper are: quant-ph
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The categories of this paper are: hep-th
32
The categories of this paper are: atom-ph
22
The categories of this paper are: chao-dyn
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The categories of this paper are: nucl-ex
34
The categories of this paper are: chem-ph
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The categories of this paper are: adap-org
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The categories of this paper are: solv-int