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[en] Tracking in high-rate experiments requires fast and radiation-resistant detectors. A suitable technology are kapton-based straw tubes operated in drift mode. We have developed a technology to construct tracking modules up to 4.5 m length utilizing short strawlets. This new type of self-supporting design using carbon-rod reinforcement offers significant advantages over previous chambers

[en] We observe evidence for a second narrow resonance in the reaction e⁺e^- → hadrons at √s around 10 GeV using the DASP detector at the DORIS storage ring. The mass of the resonance is (10.01+-.02) GeV; its width is in agreement with the storage ring resolution of approximately equal to 9 MeV. From the integrated cross section, an electronic width of Gamma sub(ee) = (0.35+-0.14) keV is derived. (orig.)

[en] We observe a narrow resonance in the reaction e⁺e^- → hadrons using the DASP detector at the DORIS storage ring. The mass is found to be (9.46 +- 0.01) GeV and the observed width is compatible with the storage ring resolution of +-8 MeV. The energy-integrated cross section results in an electronic width GAMMAsub(ee) = (1.3 +- 0.4) keV. (orig.)

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[en] The ARGUS detector came into operation at the DORIS-II e⁺s^- storage ring at the end of 1982. Its two meter long drift chamber contains 5940 sense and 24588 field wires organized in uniform 18x18.8 mm² drift cells filling the whole volume. These cells form 36 layers, 18 of which provide stereo views. Each sense wire is equipped with a single hit TDC and ADC for coordinate and dE/dx measurements. The chamber is operated with propane to improve momentum and dE/dx resolution. The drift chamber design and initial performance are presented. With a very crude space-time relation approximation and without all the necessary corrections applied a spatial resolution of about 200 μm was obtained for half of the drift cell volume. Further corrections should improve this result. An intrinsic dE/dx resolution of 4.2% and an actual resolution of 5% were obtained for cosmic muons and also for Bhabha scattered electrons. An actual dE/dx resolution of 5.6% was obtained for pions from e⁺e^- annihilation data with almost no track selection. A relativistic rise of 30% was observed in good agreement with theory. The long-term stability is still to be investigated. (orig.)

[en] The HERA-B Data Acquisition System implements a 50 kHz dead-timeless readout of 500 kB events requiring unprecedented speed of storing and data processing. The system is based on Digital Signal Processors (DSP) minimizing the number of components. A high bandwidth, low-latency DSP switching network provides full connectivity between the readout buffers and a PC farm which runs the higher level trigger. The design of the system and the achieved performance are described in this paper

[en] New data for the reaction e⁺e^- → UPSILON(9.46) have been obtained using the DASP detector at the DORIS storage ring. The electronic width GAMMAsub(ee) is (1.5 +- 0.4) keV. The branching ratio for the decay into muon pairs is (2.5 +- 2.1)%. Energy spectra for inclusive production of hadrons are given. (Auth.)