A precise measurement of the B+^+, B0^0 and mean b-hadron lifetime with the DELPHI detector at LEP I

DELPHIFinal results from the DELPHI Collaboration on the lifetime of B+ and B0 mesons and the mean b-hadron lifetime, are presented using the data collected at the Z0 peak in 1994 and 1995. Elaborate, inclusive, secondary vertexing methods have been employed to ensure a b-hadron reconstruction with good efficiency. To separate samples of B+ and B0 mesons, high performance neural network techniques are used that achieve very high purity signals. The results obtained are: tau_B+ = 1.624 +/- 0.014 (stat) +/- 0.018 (syst) ps tau_B0 = 1.531 +/- 0.021 (stat) +/- 0.031 (syst) ps tau_B+/tau_B0 = 1.060 +/- 0.021 (stat) +/- 0.024 (syst) and for the average b-hadron lifetime: tau_b = 1.570 +/- 0.005 (stat) +/- 0.008 (syst) ps

Measurement of Trilinear Gauge Couplings in e+e−e^+ e^- Collisions at 161 GeV and 172 GeV

Trilinear gauge boson couplings are measured using data taken by DELPHI at 161~GeV and 172~GeV. Values for $WWV$ couplings ($V=Z, \gamma$) are determined from a study of the reactions \eeWW\ and \eeWev, using differential distributions from the $WW$ final state in which one $W$ decays hadronically and the other leptonically, and total cross-section data from other channels. Limits are also derived on neutral $ZV\gamma$ couplings from an analysis of the reaction \eegi

Electroweak parameters of the z0 resonance and the standard model

Contains fulltext : 124399.pdf (publisher's version ) (Open Access

Prompt neutrino production in 400 GeV proton copper interactions

The prompt electron neutrino and muon neutrino fluxes from proton copper interactions at 400 GeV/c proton momentum have been measured. The asymmetry between the prompt electron (anti) neutrino and the prompt muon (anti) neutrino event rates above 20 GeV is Aeμ = (Ne - Nμ (Nc + Nμ) = 0.07 ± 0.08 corresponding to an Ne/Nμ ratio of 1.14-0.16-0.19. The cross section weighted charge asymmetry for electrons and muons combined is Aνν = 0.15 ± 0.08. The number of D decays into νe and νμ is (4.1 ± 0.9) × 10-4 per incident proton. No evidence for ντ interactions was found. © 1986