Few-Body Systems

, Volume 54, Issue 1–4, pp 271–274 | Cite as

A QCD Sum Rule Approach with an Explicit Di-quark Field



We introduce a phenomenological QCD sum rule with an explicit diquark field. We investigate certain configurations of hadrons are expected to have a good diquark structure. The parameters of the model are a diquark mass \({(m_\phi)}\) and condensate \({(\langle \phi^2\rangle)}\) . Assuming that Λ baryons can be represented by a diquark and a spectator quark configuration, we find the sum rule works well for ΛΛc, and Λb. We also find a duality relation between the mass and the condensate for which the parameter sets give good Borel curves. To maintain good Borel curve, a smaller diquark condensate is needed for an increased diquark mass. Using these parameter sets, we test the diquark structure in some hadrons which contain both good and bad diquark configurations.


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Copyright information

© Springer-Verlag 2012

Authors and Affiliations

  1. 1.Institute of Physics and Applied PhysicsYonsei UniversitySeoulKorea
  2. 2.Yukawa Institute for Theoretical PhysicsKyoto UniversityKyotoJapan

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