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arXiv · 1708.02679

Heavy-Quark Hybrid Mass Splittings: Hyperfine and "Ultrafine"

Richard F. Lebed·Eric S. Swanson
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Abstract

It is argued that the heavy-quark limit of QCD requires a certain combination of hyperfine mass splittings in heavy-quark hybrid-meson multiplets to be unusually small. This observation will assist in the exploration of the heavy-quark hybrid spectrum at facilities such as PANDA. Alternatively, a large measured value for this mass splitting indicates that at least one member of the multiplet must contain significant light-quark degrees of freedom.

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Richard F. Lebed, Eric S. Swanson. 2017-08-08. Heavy-Quark Hybrid Mass Splittings: Hyperfine and "Ultrafine". https://doi.org/10.1007/s00601-018-1376-9

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