Kasper Edwards

Measurement of the decay

Using the ARGUS detector at the e + e − storage ring DORIS II at DESY we have investigated the decays B 0 → D ∗− e + v and B 0 →D ∗− μ + ν. The B 0 mesons were produced in 39600 ϒ(4 S )→ B 0 B 0 decays. Assuming electron-muon universality we obtain a branching ratio BR ( B 0 → D ∗− e + v)= BR ( B 0 → D ∗− γm + ν)=(7.0±1.2±1.9)% .

Branching ratio and mass spectrum of the decay ϒ′ → ϒπ+π−

Abstract The reaction e + e − → ϒ ′ → ϒπ + π − , with ϒ → anything, has been measured using the ARGUS detector at DORIS . We obtain a mass difference M ( ϒ ′) − M ( ϒ ) = (562 ± 3) MeV and a decay branching ratio BR( ϒ ′→ ϒπ + π − )=(17.9±0.9±2.1)%. The invariant mass spectrum of the π + π − system differs from phase space, but is well described by a matrix element of the form ( M ππ 2 − λM π 2 ) with λ =2.6±0.5. We also report preliminary results on the exclusive decay ϒ′ → ϒπ + π − , with ϒ → e + e − , and obtain BR( ϒ → e + e − ) = (2.8 ± 0.4 ± 04±0.3)%.

Exclusive hadronic decays ofB mesons

Using the ARGUS detector at thee+e− storage ring DORIS II, we have measuredB decays into exclusive final states containing aD orD* meson plus several pions, or containing aJ/ψ or ψ′ meson plus a strange particle. Some of these channels have not been seen before, while others represent updated measurements of previous results. The branching ratios are compared with the predictions of the model of Bauer, Stech and Wirbel. Using the cleanest decay channels, the mass of the charged and neutralB meson are found to bemB−=(5280.5±1.0±2.0) MeV/c2 andmB0=(5279.6±0.7±2.0) MeV/c2 respectively, yielding a mass differencemB0−mB−=(−0.9±1.2±0.5) MeV/c2.

From Engineer-To-Order to Mass Customization

Purpose – Most mass customization literature focuses on the move from mass production to mass customization. However, in some literature engineer‐to‐order (ETO) companies are also claiming to have become mass customizers, although it can be questioned if these companies conform to popular definitions of mass customizers. The purpose of this paper is to ask the question: under which conditions is it reasonable to label ETO companies as mass customizers?Design/methodology/approach – First, definitions of mass customization are examined and related to ETO companies that move towards mass customization. Second, the individual transitions from mass production and ETO to mass customization are analyzed by: relating the transition to classifications from relevant literature; describing the motivations and risks associated with the transition; and defining some of the most important transition characteristics. Finally it is discussed if ETO companies can become mass customizers and under which conditions it would...

An Improved Upper Limit on the tau-neutrino Mass from the Decay tau- ---> pi- pi- pi- pi+ pi+ tau-neutrino

Abstract Using the ARGUS detector at the e + e − storage ring DORIS II, we have observed the decay τ − → π − π − π − π + π + ν τ in tau-pair events produced at center-or-mass energies between 9.4 and 10.6 GeV. From the 5π invariant mass distribution we derive an upper limit of m ( ν τ ) c 2 at the 95% confidence level. The branching ratio for this decay channel is found to be (0.064±0.023±0.01)%.

Observation of spin-parity 2+ dominance in the reactionγγ→ρ0ρ0 near threshold

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.

Measurement of tau decays into three charged pions

We report a study of the decay τ−→τ−τ+τ−vτ using the ARGUS detector at the DORIS II storage ring. Tau pairs were produced bye+e− annihilation at centre-of-mass energies near 10 GeV. We have observed about 1,700 events, corresponding to a branching ratio for τ−→τ−τ+τ−vτ of (5.6±0.7)%. The dominant mode for this decay is observed to beρ0π− in aJp=1+ spin state. Theρ0π− mass spectrum shows a broad enhancement near 1.10 GeV/c2, which has the properties expected for theA1.

Inclusive production ofD0,D+ andD*(2010)+ mesons inB decays and nonresonante+e− annihilation at 10.6 GeV

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.

A partial wave analysis of the decay D0 → KS0π+π−

Abstract Using the ARGUS detector at the DORIS-II electron-positron storage ring at DESY, we have investigated the exclusive decay D ∗+ → D 0 π + , D 0 → K S 0 π + π − . From a partial wave analysis of the KS0π+π− system we find that (71.8± 4.2 ± 3.0)% are D 0 → K ∗− π + and (22.7 ± 3.2 ± 0.9)% are D 0 → K 0 ϱ 0 with a relative phase of (−137 ± 7 ± 3)° between the channels. The remaining fraction can be described by several channels involving excited resonances, but not by a three-body phase space decay, thus giving first evidence for D0 decays into K 0 ∗ (1430) − π + , K 0 f 0 (1975), K 0 f 2 (1270) , and K 0 f 0 (1400) .

Reconstruction of B mesons

Abstract B mesons have been reconstructed in five decay channels of the type B →D ∗ ±nπ(n=1,2,3) using data accumulated by the ARGUS experiment at the e + e − storage ring DORIS II at DESY. In total, we find 40 neutral B mesons above a background of 15±6 events with a mass of (5278.2±1.0±3.0) MeV/ c 2 and 32 charged B mesons above a background of 17±6 events with a mass of (5275.8±1.3±3.0) MeV/ c 2 . The decays B 0 D ∗+ π − π 0 , B 0 D ∗+ π − π − π + , and B − → D ∗+ π − π − π 0 have been observed for the first time. We find substantially smaller branching ratios for the decay modes B 0 → D ∗+ π − and B − → D ∗+ π − π − than previously published by the CLEO collaboration.