Masses of open-flavour heavy-light hybrids from QCD sum-rules

  • J. Ho
  • D. Harnett
  • T. G. Steele
Open Access
Regular Article - Theoretical Physics


We use QCD Laplace sum-rules to predict masses of open-flavour heavy-light hybrids where one of the hybrid’s constituent quarks is a charm or bottom and the other is an up, down, or strange. We compute leading-order, diagonal correlation functions of several hybrid interpolating currents, taking into account QCD condensates up to dimension-six, and extract hybrid mass predictions for all J P ∈ {0± , 1±}, as well as explore possible mixing effects with conventional quark-antiquark mesons. Within theoretical uncertainties, our results are consistent with a degeneracy between the heavy-nonstrange and heavy-strange hybrids in all J P channels. We find a similar mass hierarchy of 1+, 1, and 0+ states (a 1+ state lighter than essentially degenerate 1 and 0+ states) in both the charm and bottom sectors, and discuss an interpretation for the 0 states. If conventional meson mixing is present the effect is an increase in the hybrid mass prediction, and we estimate an upper bound on this effect.


QCD Phenomenology 


Open Access

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© The Author(s) 2017

Authors and Affiliations

  1. 1.Department of Physics and Engineering PhysicsUniversity of SaskatchewanSaskatoonCanada
  2. 2.Department of PhysicsUniversity of the Fraser ValleyAbbotsfordCanada

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