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Lepton Universality Test in Upsilon(1S) decays at BaBar

High Energy Physics - Experiment 2019-08-13 v1

Abstract

Using a sample of 122 million Upsilon(3S) decays collected with the BaBar detector at the PEP-II asymmetric energy collider at the SLAC National Accelerator Laboratory, we measure the ratio R_taumu=BR(Upsilon(1S)->tau^+tau^-)/BR(Upsilon(1S)->mu^+mu^-); the measurement is intended as a test of lepton universality and as a possible search for a light pseudoscalar Higgs boson in Next to Minimal Supersymmetric Standard Model (NMSSM) scenarios. Such a boson could appear in a deviation of the ratio R_taumu from the Standard Model expectation, that is 1, except for small lepton mass corrections. The analysis exploits the decays Upsilon(3S) -> Upsilon(1S) pi^+pi^-, Upsilon(1S) -> l^+l^-, where l = mu, tau.

Keywords

Cite

@article{arxiv.0910.0423,
  title  = {Lepton Universality Test in Upsilon(1S) decays at BaBar},
  author = {Elisa Guido},
  journal= {arXiv preprint arXiv:0910.0423},
  year   = {2019}
}

Comments

5 pages, 4 figures. To be published in the proceedings of DPF-2009, Detroit, MI, July 2009, eConf C090726

R2 v1 2026-06-21T13:53:29.697Z