Search for pair production of a new b' quark that decays into a Z boson and a bottom quark with the ATLAS detector.

Journal article

A search is reported for the pair production of a new quark b' with at least one b' decaying to a Z boson and a bottom quark. The data, corresponding to 2.0 fb(-1) of integrated luminosity, were collected from pp collisions at √s = 7 TeV with the ATLAS detector at the CERN Large Hadron Collider. Using events with a b-tagged jet and a Z boson reconstructed from opposite-charge electrons, the mass distribution of large transverse momentum b' candidates is tested for an enhancement. No evidence for a b' signal is detected in the observed mass distribution, resulting in the exclusion at a 95% confidence level of b' quarks with masses m (b') < 400 GeV that decay entirely via b' → Z+b. In the case of a vectorlike singlet b' mixing solely with the third standard model generation, masses m(b') < 358 GeV are excluded.

Authors: Aad, G; Abbott, B; Abdallah, J; Abdel Khalek, S; Abdelalim, A

• Publication status: Published
• Journal: Physical Review Letters
• Volume: 109
• Issue: 7
• Pages: 071801
• Publication date: 2012-08-16
• DOI: 10.1103/physrevlett.109.071801
• EISSN: 1079-7114
• ISSN: 0031-9007
• Language: English
• Keywords: ATLAS Collaboration