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Riddle of the scalars: where is the sigma?

M. R. Pennington
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Abstract

The riddle of the sigma is recast in a way that tries to differentiate fact from fiction as a basis for future/further discussion. By doing this, it is hoped that the role of the sigma as dominating the ubiquitous $ππ$ interactions below 1 GeV and its relation to the QCD vacuum can be clarified.

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M. R. Pennington. 1999-05-13. Riddle of the scalars: where is the sigma?. https://arxiv.org/abs/hep-ph/9905241

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