Production of charged particles, KS 0, K±, p and Λ in Z → bb events and in the decay of b hadrons
Physics Letters B 347:3-4 (1995) 447-466
Abstract:
A sample of events enriched in bb̄ quark pairs was selected in the data recorded by the DELPHI experiment at LEP during 1992 and 1993, by the presence of secondary decay vertices from short-lived particles. Using this sample, the average multiplicities of Ks0, K±, p(p̄), Λ(Λ) and of charged particles in bb̄ events have been measured, distinguishing the component from fragmentation and the component coming from the decay of b-hadrons. The measurement of the average charge multiplicity in bb̄ events was used to compute the mean fractional beam energy carried by the primary b-hadron, and the difference in charged particle multiplicity between bb̄ events and light quark (uū, dd̄, ss̄) events. © 1995.A measurement of B+ and B0 lifetimes using {Mathematical expression} events
Zeitschrift für Physik C Particles and Fields 68:1 (1995) 13-23
Abstract:
A measurement of B meson lifetimes is presented using data collected from 1991 to 1993 by the DELPHI detector at the LEP collider. Samples of events with a D meson and a lepton in the same jet are selected where {Mathematical expression} and D*ℓ+ events originate mainly from the semileptonic decays of B+ and B0 mesons, respectively. From the reconstructed B decay length and the estimated B momentum, taking into account the dilution due to B decays into {Mathematical expression}, the following B meson lifetimes and lifetime ratio are measured: {Mathematical expression} and an average lifetime of B+ and B0 mesons is obtained: {Mathematical expression} © 1995 Springer-Verlag.First measurement of the strange quark asymmetry at the Z0 peak
Zeitschrift für Physik C Particles and Fields 67:1 (1995) 1-13
Abstract:
A measurement of the strange quark forward-backward asymmetry at the Z0 peak was performed using 718,000 multihadronic Z0 decays collected by the DELPHI detector at LEP in 1992. The s-quark was tagged by the presence of high momentum charged kaons identified by the Ring Imaging Cherenkov detector and by Λ0;s decaying into pπ-. The s-quark purity obtained was estimated for the two hadrons to be 43%. The average s-quark asymmetry was found to be 0.131±0.035 (stat.) ±0.013 (syst.). The forward-backward asymmetry was measured for unresolved d-and s-quarks, tagged by the detection of a high energy neutron or neutral kaon in the Hadron Calorimeter. The combined d-and s-quark purity was 69% and their asymmetry was found to be 0.112±0.031 (stat.) ±0.054 (syst.). © 1995 Springer-Verlag.Jet production in high Q2 deep-inelastic ep scattering at HERA
Zeitschrift für Physik C Particles and Fields 67:1 (1995) 81-92
Abstract:
Two-jet production in deep-inelastic electron-proton scattering has been studied for 160Measurement of multiplicity and momentum spectra in the current fragmentation region of the Breit frame at HERA
Zeitschrift für Physik C Particles and Fields 67:1 (1995) 93-107