Observation of a New X-b State in Radiative Transitions to Y(1S) and Y(2S) at ATLAS

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Aad G., Abbott B., Abdallah J., Abdelalim A. A., Abdesselam A., Abdinov O., ...More

PHYSICAL REVIEW LETTERS, vol.108, no.15, 2012 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 108 Issue: 15
  • Publication Date: 2012
  • Doi Number: 10.1103/physrevlett.108.152001
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Middle East Technical University Affiliated: Yes


The chi(b)(np) quarkonium states are produced in proton-proton collisions at the Large Hadron Collider at root s=7 TeV and recorded by the ATLAS detector. Using a data sample corresponding to an integrated luminosity of 4.4 fb(-1), these states are reconstructed through their radiative decays to Y(1S,2S) with Y ->mu(+)mu(-). In addition to the mass peaks corresponding to the decay modes chi(b)(1P,2P)-> Y(1S)gamma, a new structure centered at a mass of 10.530 +/- 0.005(stat)+/- 0.009(syst) GeV is also observed, in both the Y(1S)gamma and Y(2S)gamma decay modes. This structure is interpreted as the chi(b)(3P) system.