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Lifetimes of charged and neutral B hadrons using event topology

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Adam, W. [--] Cortina Gil, Eduardo [UCL] DELPHI Collaboration [--]

The lifetimes of charged and neutral B hadrons have been measured using data collected by the DELPHI experiment at LEP between 1991 and 1993. B hadrons are tagged as jets with a secondary vertex and the charge of the B candidate is taken to be the sum of the charges of the particles in the secondary vertex. Approximately 1,434,000 multihadronic Z0 decays yielded 1817 B hadron candidates. The B purity was estimated to be around 99.1±0.3%, and 83% (70%) of the events measured as neutral (charged) came from neutral (charged) B's. The mean lifetimes of charged and neutral B hadrons were found to be 1.72±0.08 (stat.) ±0.06 (syst.) ps and 1.58±0.11 (stat.)±0.09 (syst.) ps respectively. The ratio of their lifertimes, τcharged/τneutral, was 1.09 −0.10 +0.11 (stat.)±0.08 (syst.). By making assumptions about the B s 0 and Λ b 0 states, the B+ and B0 meson lifetimes were determined to be τB+ = 1.72 ± 0.08 (stat.) ±0.06 (syst.) ps and τB+ = 1.63 ± 0.14 (stat.)±0.13 (syst.) ps and the ratio of their lifetimes was: τB+/τB0 = 1.06 −0.11 +0.13 ±0.10. The mean B lifetime was also deduced to be < τ > = 1.64 ±0.06 (stat.)±0.04 (syst.) ps.

Document type Article de périodique (Journal article) – Article de recherche
Access type Accès libre
Publication date 1995
Language Anglais
Journal information "Zeitschrift für Physik. C, Particles and fields" - Vol. 68, no.3, p. 363-374 (1995)
Publisher Springer (Berlin)
issn 0170-9739
e-issn 1431-5858
Publication status Publié
Affiliation UCL - SST/IRMP - Institut de recherche en mathématique et physique
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Bibliographic reference Adam, W. ; Cortina Gil, Eduardo ; DELPHI Collaboration ; et. al. Lifetimes of charged and neutral B hadrons using event topology . In: Zeitschrift für Physik. C, Particles and fields, Vol. 68, no.3, p. 363-374 (1995)
Permanent URL http://hdl.handle.net/2078.1/126533