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arXiv · 1007.4682

Extracting the light quark mass ratio m_u/m_d from bottomonia transitions

Feng-Kun Guo·Christoph Hanhart·Ulf-G. Meißner
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Abstract

We propose a new method to extract the light quark mass ratio $m_u/m_d$ using the $Υ(4S)\to h_bπ^0(η)$ bottomonia transitions. The decay amplitudes are dominated by the light quark mass differences, and the corrections from other effects are rather small, allowing for a precise extraction. We also discuss how to reduce the theoretical uncertainty with the help of future experiments. As a by-product, we show that the decay $Υ(4S)\to h_bη$ is expected to be a nice channel for searching for the $h_b$ state.

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Feng-Kun Guo, Christoph Hanhart, Ulf-G. Meißner. 2010-10-15. Extracting the light quark mass ratio m_u/m_d from bottomonia transitions. https://doi.org/10.1103/physrevlett.105.162001%2010.1103%2Fphysrevlett.105.162001%2010.1103%2Fphysrevlett.105.162001

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