Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: LFV couplings of the extra gauge boson Z' and leptonic decay and
  production of pseudoscalar mesons   Considering the constraints of the lepton flavor violating (LFV) processes
$\mu \rightarrow 3e$ and $\tau\rightarrow3\mu$ on the LFV couplings
$Z'\ell_{i}\ell_{j}$, in the contexts of the $E_{6}$ models, the left-right
(LR) models, the "alternative" left-right (ALR) models and the 331 models, we
investigate the contributions of the extra gauge boson $Z'$ to the decay rates
of the processes $\ell_{i}\rightarrow\ell_{j}\nu_{\ell}\nu_{\ell}$,
$\tau\rightarrow\mu P $ and $P\rightarrow \mu e$ with $P=\pi^{0},\eta$ and
$\eta '$. Our numerical results show that the maximal values of the branching
ratios for these processes are not dependent on the $Z'$ mass $M_{Z'}$ at
leader order. The extra gauge boson $Z'_{X}$ predicted by the $E_{6}$ models
can make the maximum value of the branching ratio
$Br(\tau\rightarrow\mu\nu_{\ell}\nu_{\ell})$ reach $1.1\times10^{-7}$. All $Z'$
models considered in this paper can produce significant contributions to the
process $\tau\rightarrow\mu P$. However, the value of $Br(P\rightarrow\mu e)$
is far below its corresponding experimental upper bound.

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The categories of this paper are: nucl-ex
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The categories of this paper are: stat
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The categories of this paper are: quant-ph
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The categories of this paper are: solv-int
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The categories of this paper are: chem-ph
36
The categories of this paper are: cmp-lg
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The categories of this paper are: ao-sci
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The categories of this paper are: acc-phys
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The categories of this paper are: math
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The categories of this paper are: nucl-th
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The categories of this paper are: math-ph
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The categories of this paper are: cond-mat
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The categories of this paper are: q-bio
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The categories of this paper are: astro-ph
30
The categories of this paper are: q-alg
35
The categories of this paper are: mtrl-th