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arXiv · 0912.2147

Study of $π^{0}$ and $η$ decays containing dilepton

Chong-Chung Lih
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Abstract

We calculate the momentum dependent form factors of $P \to γ^* γ^*$($P=π^{0}, η$) within the light-front quark model. Using the form factors, we examine the decays of $P \to l^+ l^-$, $P \to l^+ l^- γ$ and $P \to l^+ l^- l^+ l^-$($l=e$ or $μ$) and compare our results with the experimental data and other theoretical predictions. In particular, for $π^0 \to e^+e^-$, we find that the decay branching ratio is $6.68\times 10^{-8}$, which is consistent with the recent measurement of $(7.48\pm0.29\pm0.25)\times 10^{-8}$ by E799 of KTeV/Fermilab.

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Chong-Chung Lih. 2010-10-20. Study of $π^{0}$ and $η$ decays containing dilepton. https://doi.org/10.1088/0954-3899%2F38%2F6%2F065001

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