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arXiv · 0803.4493

On mass corrections to the decays P \to l^+l^-

A. E. Dorokhov·M. A. Ivanov
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Abstract

We use the Mellin-Barnes representation in order to improve the theoretical estimate of mass corrections to the width of light pseudoscalar meson decay into a lepton pair, $P\to l^+l^-$ . The full resummation of the terms $\ln(m_l^2/Λ^2)(m_l^2/Λ^2)^n$ and $(m_l^2/Λ^2)^n$ to the decay amplitude is performed, where $m_l$ is the lepton mass and $Λ\approx m_ρ$ is the characteristic scale of the $P\toγ^*γ^*$ form factor. The total effect of mass corrections for the $e^+e^-$ channel is negligible and for the $μ^+μ^-$ channel its order is of a few per cent.

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A. E. Dorokhov, M. A. Ivanov. 2008-04-19. On mass corrections to the decays P \to l^+l^-. https://doi.org/10.1134/s0021364008100032

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