par Abdallah, Jalal Mohamad J.;Alderweireld, Thomas;Bertrand, Daniel 
;D'Hondt, Jorgen;De Clercq, Catherine;Lemonne, Jacques ;Van Lysebetten, Ann;Van Remortel, Nick;Wickens, John H. ; [et al.]
Référence European Physical Journal C. Particles and Fields, 35, 1, page (35-52)
Publication Publié, 2004-06
;D'Hondt, Jorgen;De Clercq, Catherine;Lemonne, Jacques ;Van Lysebetten, Ann;Van Remortel, Nick;Wickens, John H. ; [et al.]Référence European Physical Journal C. Particles and Fields, 35, 1, page (35-52)
Publication Publié, 2004-06
Article révisé par les pairs
| Résumé : | Oscillations in the Bs 0-Bs 0 system were studied in events selected from about 4.3 million hadronic Z 0 decays registered by DELPHI between 1992 and 2000. This paper presents updates of two published analyses ([11,12]). The first analysis, which utilizes leptons emitted with large momentum transverse to a jet, was improved by means of a better algorithm for the vertex reconstuction and a new algorithm for flavour-tagging at production time. The second analysis, which utilizes Ds-lepton events, was improved by optimizing the treatment of proper time resolution. No signal of B0 oscillations was observed and limits on the mass difference between the physical B0 states were obtained to be: δms > 8.0ps-1 at the 95% C.L. with a sensitivity of δms = 9.1 ps-1 in the high pt lepton analysis and δms < 4.9 ps-1 at the 95% C.L. with a sensitivity of δms = 8.6 ps-1 in the D s-lepton analysis. Previously published results on these analyses are superseded. The combination of these results with those obtained in other independent analyses previously performed in DELPHI (Ds-hadron, exclusive Bs 0, inclusive vertex) gives: δm, > 8.5 ps-1 at the 95% C.L. with a sensitivity of δms = 12.0 ps-1. |
