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

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.

Version to appear in Few-Body Systems. Substantial modifications from previous version, including extensive additional references and an expanded discussion of relevant operators. 7 pages

References in corpus (8)

• Heavy-Quark QCD Exotica
• Hybrid Mesons
• Spin-dependent potentials from lattice QCD
• Heavy Quarkonium Hybrids: Spectrum, Decay and Mixing
• The Born-Oppenheimer approximation in an effective field theory language
• Effective string theory and the long-range relativistic corrections to the quark-antiquark potential
• Quarkonium $h$ States As Arbiters of Exoticity
• $P-$state Positronium for Precision Physics: an Ultrafine Splitting at ${\alpha }^6$

Cited by in corpus (6)

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• The Dynamical Diquark Model: First Numerical Results
• Nonrelativistic effective field theory for heavy exotic hadrons
• Heavy Hybrid Decays in a Constituent Gluon Model
• ${\chi }_b(3P)$ Multiplet Revisited: Ultrafine Mass Splitting and Radiative Transitions
• Can the hyperfine mass splitting formula in heavy quarkonia be applied to the $B_c$ system?