Showing papers by "Hermann Kolanoski published in 1991"
TL;DR: In this article, the authors used the ARGUS detector at the e+ e− storage ring DORIS II at DESY to search for direct evidence for b→u transitions through reconstruction of complete events.
50 citations
TL;DR: In this article, the ARGUS detector at the DESY storage ring was used to measure the production of mesons in B decays and in nonresonante+e− annihilation around 10.6 GeV.
Abstract: Using the ARGUS detector at thee+e− storage ring DORIS II at DESY, we have measured the inclusive production ofD0,D+ andD*(2010)+ mesons inB decays and in nonresonante+e− annihilation around 10.6 GeV. The inclusive branching ratios forB decays toD0,D+ andD*+ mesons are found to be (52.2±8.2±3.5)%, (27.2±6.3±3.5)% and (34.8±6.0±3.5)% respectively. Thus,D0 andD+ production account for about 70% of the charm produced inB decays, neglectingb→u contributions to the total width. The production cross sections and momentum spectra for continuume+e− annihilation are also presented.
40 citations
Technical University of Dortmund1, University of Erlangen-Nuremberg2, Heidelberg University3, Max Planck Society4, Natural Sciences and Engineering Research Council5, National Science Foundation6, Karlsruhe Institute of Technology7, University of Ljubljana8, Swedish Research Council9, United States Department of Energy10
TL;DR: Using the ARGUS detector at the e + e − storage ring DORIS II at DESY, a search for penguin decays of B mesons involving b→s gluon has been performed as mentioned in this paper.
35 citations
TL;DR: In this article, the ARGUS detector at the DORIS II e+e− storage ring was used to detect the semileptonic decay of Λc+ in the decay channels Λ c+→Λe+X and Λ C+→ Λμ+X.
22 citations
Technical University of Dortmund1, University of Erlangen-Nuremberg2, Heidelberg University3, Max Planck Society4, Natural Sciences and Engineering Research Council5, National Science Foundation6, Karlsruhe Institute of Technology7, University of Ljubljana8, Swedish Research Council9, United States Department of Energy10
TL;DR: Using the ARGUS detector at the e + e − storage ring DORIS II at DESY, penguin decays of B mesons involving b→sX + X − have been searched for, where X is one of e, μ, π, or K as mentioned in this paper.
21 citations
15 Nov 1991-Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment
TL;DR: In this article, the authors measured spatial resolutions in a quadratic drift cell using as drift gas pure DME or a mixture of 70% He and 30% DME at atmospheric pressure.
Abstract: We have measured spatial resolutions in a quadratic drift cell using as drift gas pure DME or a mixture of 70% He and 30% DME at atmospheric pressure. For a maximum drift distance of 5 mm we obtained in the He-DME mixture a resolution σ r = 80 μ m over 60% of the drift cell and for pure DME σ r = 40 μ m over 80% of the drift cell. The drift velocity of electrons is approximately three times faster in this mixture than in pure DME. A systematic study of the electric field dependence of the drift velocities in various He-DME mixtures is also presented.
17 citations
TL;DR: In this paper, a spin-parity analysis shows a dominance of the partial wave (JP,Jz)=(2+, 2) with a small admixture from JP=0+. The contribution of negative parity states is consistent with zero.
Abstract: The reactionγγ→π+π−π+π− has been studied with the ARGUS detector. The rate in the invariant mass region below 1.8 GeV/c2 is found to be largely due toρ0ρ0 production. A spin-parity analysis shows a dominance of the partial wave (JP,Jz)=(2+, 2) with a small admixture fromJP=0+. The contribution of negative parity states is consistent with zero. The large ratio of cross sectionsσ(γγ→ρ0ρ0)/σ(γγ→ρ+ρ−)≃4, and the dominance of theJP=2+ wave in the reactionγγ→ρ0ρ0 is a signature consistent with the production of an exotic (I=2) resonance.
17 citations
Technical University of Dortmund1, University of Erlangen-Nuremberg2, University of Hamburg3, Heidelberg University4, Max Planck Society5, Natural Sciences and Engineering Research Council6, Karlsruhe Institute of Technology7, University of Ljubljana8, Swedish Research Council9, United States Department of Energy10
TL;DR: In this article, a spin-parity analysis of the ϱ + ϱ − system in the reaction γγ→ϱ+ ϱ− → Π + Π − Π 0 Π 1 has been performed using the ARGUS detector at the e + e − storage ring DORIS II at DESY.
16 citations
TL;DR: In this article, the authors used the ARGUS detector at the e + e − storage ring DORIS II at DESY to study semileptonic charmed meson decays through ǫ − and K ∗0 -electron correlations in continuum production.
15 citations
Technical University of Dortmund1, University of Erlangen-Nuremberg2, University of Hamburg3, Heidelberg University4, Max Planck Society5, Natural Sciences and Engineering Research Council6, Karlsruhe Institute of Technology7, University of Ljubljana8, Swedish Research Council9, United States Department of Energy10
TL;DR: In this article, an analysis of the decay τ− → π−π−π+π0ντ has been performed with the ARGUS detector at the DORIS II storage ring.
12 citations