Resonant structure and flavor tagging in the B pi+- system using fully reconstructed B decays

Collaboration
Feb, 1998
13 pages
Published in:
  • Phys.Lett.B 425 (1998) 215-226
Report number:
  • CERN-EP-98-017,
  • CERN-EP-98-17
Experiments:

Citations per year

1998200520122019202402468
Abstract: (Elsevier)
Starting from a sample of four million hadronic Z decays collected with the ALEPH detector at LEP, 404 charged and neutral B mesons are fully reconstructed and used to look for resonant structure in the Bπ system. An excess of events is observed above the expected background in the Bπ mass spectrum at a mass ≈5.7 GeV/c 2 , consistent with the production and decay to B (∗) π of the B ∗∗ states predicted by Heavy Quark Symmetry (HQS). In the framework of HQS, it is found that the mass of the B 2 ∗ state is (5739 + 8 −11 ( stat ) +6 −4 ( syst )) MeV/c 2 and the relative production rate of the B ∗∗ system is BR(b→B ∗∗ →B (∗) π)/BR(b→B u,d )=(31±9 (stat) +6 −5 (syst)) % . In the same sample of B mesons, significant Bπ ± charge-flavour correlations are observed, which may prove important for tagging the initial B state in future CP violation studies.