European Physical Journal C: Particles and Fields (Jan 2019)

Remarks on the heavy-quark flavour symmetry for doubly heavy hadronic molecules

  • V. Baru,
  • E. Epelbaum,
  • J. Gegelia,
  • C. Hanhart,
  • U.-G. Meißner,
  • A. V. Nefediev

DOI
https://doi.org/10.1140/epjc/s10052-019-6560-7
Journal volume & issue
Vol. 79, no. 1
pp. 1 – 7

Abstract

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Abstract The possibility for a common effective field theory for hadronic molecules with different heavy-quark flavours is examined critically. It is argued that such a theory does not allow one to draw definite conclusions for doubly heavy molecules. In particular, it does not allow one to relate binding energies for the molecules in the c-quark and b-quark sectors with controlled uncertainties. Therefore, while this kind of reasoning does not preclude from employing heavy-quark spin symmetry for charmonium- and bottomonium-like states separately within a well established effective field theory framework, relations between different heavy-quark sectors can only be obtained using phenomenological approaches with uncontrolled uncertainties.