[en] The Solenoid Detector Collaboration (SDC) has proposed to construct and operate a large, general-purpose, solenoidal detector that combines excellent charged particle detection, a hermetic, scintillator-based calorimeter and a large muon identification system. A principal component of the SDC detector is the outer tracker that provides precise momentum measurement of charged particles from a radius of 85 cm to 165 cm from the proton beam. The outer tracker front-end electronics capture and digitize the data it produces and a data collection circuit (DCC) collects this data and passes it to the SDC data acquisition (DAQ) system. The authors describe in this article the specifications and design of the outer tracker DCC

[en] We evaluate the use of a fast proximity focussing ring imaging Cherenkov (RICH) system for use in the CDF detector in a pp environment. The evolving emphasis of the collaboration towards B-physics requires particle identification beyond the capabilities of the current detector. We also report on the production of, and our first experiences with, sprayed CsI photocathodes. (orig.)

[en] The detector ARGUS has been designed as a universal tool to investigate final states from e⁺e^- annihilation processes in the energy range of the Υ resonances. ARGUS started operation in October 1982 and has since successfully taken data at the Υ(1S), Υ(2S) and Υ(4S) energies, and in the nearby continuum. The detector combines excellent charged particle identification and good photon energy resolution over more than 90% of the full solid angle. A particle originating from the interaction vertex and leaving the beam tube traverses the following components: The vertex drift chamber, the main drift chamber which determines its momentum and specific ionization, the time-of-flight system through which its velocity is determined, and the electromagnetic calorimeter. Muons pass through the magnet coils and the flux return yoke and finally hit the muon chamber system which surrounds the detector. The momentum resolution of ARGUS is σ(p_T)/p_T = (0.01²+(0.009p_T[GeV/c])²)^1/2, and the photon energy resolution in the barrel shower counters is σ(E)/E = (0.072²+0.065²/E[GeV])^1/2. Combining the information from all particle identification devices, more than 80% of all charged hadrons can be recognized unambiguously. The electron-hadron and muon-hadron rejection rates are 1:200 and 1:50 respectively. (orig.)

[en] We report on a high precision measurement of Φ-meson production in continuum events and in direct decays of the Υ(1S)- and Υ(2S)-mesons. The ratio of the total production rate of Φ-mesons in direct Υ(1S)- and Υ(2S)-decays over that in continuum events is 1.32±0.08±0.09 and 1.07±0.13±0.11 respectively. This is compatible with the corresponding ratio obtained for lighter mesons, but is appreciably smaller than the relative baryon production rate. (orig.)

[en] A search for two exotic decay modes of the Υ(1S) meson has been made using the ARGUS detector at the e⁺e^- storage ring DORIS II at DESY. The first was Υ(1S) decays into weakly interacting particles, for which an upper limit of 2.3% at the 90% CL on the branching ratio is found. The second mode was Υ(1S)→γa, where a is a neutral particle with mass less than 1.5 GeV/c², that either decays inside the detector or is sufficiently long-lived to escape detection. For short-lived particles a decaying into an e⁺e^- pair, upper limits on the BR(Υ(1S)→γa) of 3.1x10^-4 at the 90% CL are found. The upper limit without restriction on the lifetime of a is found to be 1.3x10^-3. Limits for other decay modes are also given. (orig.)

[en] Using the ARGUS detector at the e⁺e^- storage ring DORIS II, we have observed inclusive D_S production, using the channel D_S^- → φπ^-, in decays of B mesons produced on the Υ(4S). The product of branching ratios BR(D → D_SX).BR(D_S^- → φπ^-) is (4.2±0.9±0.6)x10^-3. The D_S momentum spectrum suggests a substantial two-body component to the final states of B → D_SX decays. (orig.)

[en] The final states K_S⁰K_S⁰π⁺π^- and K_S⁰K^-+π⁰π^±, produced in two-photon reactions, have been studied using the ARGUS detector at the e⁺e^- storage ring DORIS II at DESY. The reaction γγ → K^*+K^*- has been observed for the first time. Its cross section is about eight times larger than that for γγ → K^*0anti K^*0, but it has a similar W_γγ dependence. (orig.)

[en] Using the ARGUS detector at DORIS II, the decay of F⁺→anti K^*0K⁺, and the ratio BR(F⁺→anti K^*0K⁺)/BR(F⁺→Φπ⁺) is found to be 1.44±0.37. This is a substantial rate for a decay channel which cannot proceed via a colour-favoured diagram. (orig.)

[en] Using the ARGUS detector at the e⁺e^- storage ring DORIS II at DESY, we have measured the lifetimes of the D⁰, D⁺ and D_s⁺ mesons. We find τsub(D⁰) = (4.8±0.4±0.3)x10^-13 s, τsub(D⁺) = (10.5±0.8±0.7)x10^-13 s and τsub(D_s⁺) = (5.6_-1.2⁺1.3±0.8)x10.¹³s. (orig.)

[en] We have searched for neutrinoless tau decays into three charged particles as evidence for lepton-flavour or lepton-number violation. The data were collected using the ARGUS detector at the DORIS II storage ring. Tau pairs were produced by e⁺e^- annhilation at centre-of-mass energies near 10 GeV. No evidence for lepton-number or lepton-flavour violation was observed, but the upper limits obtained are an order of magnitude lower than those previously published. (orig.)