European Physical Journal C: Particles and Fields (Jun 2020)

Bottomonium spectrum with a Dirac potential model in the momentum space

  • David Molina,
  • Maurizio De Sanctis,
  • César Fernández-Ramírez,
  • Elena Santopinto

DOI
https://doi.org/10.1140/epjc/s10052-020-8099-z
Journal volume & issue
Vol. 80, no. 6
pp. 1 – 12

Abstract

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Abstract We study the bottomonium spectrum using a relativistic potential model in the momentum space. This model is based on a complete one gluon exchange interaction with a momentum dependent screening factor to account for the effects due to virtual pair creation that appear close to the decay thresholds. The overall model does not make use of nonrelativistic approximations. We fit well established bottomonium states below the open bottom threshold and predict the rest of the spectrum up to $$\approx 11200$$ ≈11200 MeV and $$J^{PC}=3^{--}$$ JPC=3-- . Uncertainties are treated rigorously and propagated in full to the parameters of the model using a Monte Carlo to identify if which deviations from experimental data can be absorbed into the statistical uncertainties of the models and which can be related to physics beyond the $$b\bar{b}$$ bb¯ picture, guiding future research. We get a good description of the spectrum, in particular the Belle measurement of the $$\eta _b(2S)$$ ηb(2S) state and the $$\varUpsilon (10860)$$ Υ(10860) and $$\chi _b(3P)$$ χb(3P) resonances.