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Isospin Symmetry Breaking in ρ\toπγDecay

Xiao-Jun Wang·Ji-Hao Jiang·Mu-Lin Yan
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Abstract

In terms of effective field theory and mixed propagator approach, we show that there is a larger hidden effect of isospin breaking in $ρ^0\toπ^0γ$ decay due to an $ω$ exchange, $ρ^0\toω\toπ^0γ$. The branching ratio is predicted as $B(ρ^0\toπ^0γ)=(11.67\pm 2.0)\times 10^{-4}$, which is much larger than Partcile Data Group's datum $(6.8\pm 1.7)\times 10^{-4}$ and one of charged mode, $B(ρ^\pm\toπ^\pmγ)=(4.5\pm 0.5)\times 10^{-4}$.

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Xiao-Jun Wang, Ji-Hao Jiang, Mu-Lin Yan. 2002-04-05. Isospin Symmetry Breaking in ρ\toπγDecay. https://arxiv.org/abs/hep-ph/0101166

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