[en] The author measures cross-section times branching fractions for six Cabbibo favored decay modes of the D meson and compare them to previous experiments. Absolute branching fractions are measured for two decay modes (D⁰ → K/sup -/π/sup +/ and D/sup +/ → K/sup -/π/sup +/π/sup +/) using completely reconstructed events and the results suggest higher numbers than have been previously measured using methods which require knowledge of the cross-section

[en] Recent charm experiments have used high statistic data samples to search for D meson mixing and CP violation in charme decays. In contrast to the strange and bottom sectors, Standard Model contributions to charm mixing and CP violation are expected to be below experimental sensitivity, so that effects of New Physics may be discernible. This situation provides a unique environment for the search for New Physics. The next generation of charme experiments expects to extend the searches with data samples which are an order of magnitude larger still

[en] When W bosons are produced in proton-antiproton collisions, they are often accompanied by initial state gluon radiation which provides a transverse momentum boost to the W. With the UA2 detector at the CERN proton-antiproton collider the inclusive p_T^W spectrum has been measured and compared with the theoretically predicted spectrum. A data set of 2.5 pb^-1 is analyzed from the 1988 collider run which provides a sample of 686 W → eν candidates with an expected background from QCD processes of 10-30 events. Qualitative agreement between data and theory is observed. (K.A.) 8 refs.; 8 figs

[en] Radioactive and chemical tracers offer some unique advantages in detailed flow measurement on steam turbine plant. A series of experiments on a nuclear power station are reported where tracers successfully measured water flow rates and the initial steam moisture with an accuracy suitable for performance and commissioning tests. Both radioactive and chemical tracer methods produced identical results. Straightforward practical procedures were evolved that ensured repeatable accuracy and in addition a quantitative method of detecting heater leaks on load was established. (author)

[en] The UA2 detector has recently undergone an extensive upgrading program in preparation for running with the new ACOL anti-proton source at the CERN SPS Collider. This upgrade required a corresponding improvement in the performance of the data acquisition and trigger systems. In particular, a new front-end system, including three levels of event selection in a hierarchical trigger system, and two stages of event processing and buffering, has been constructed. In this contribution, we describe the overall structure of the new data acquisition system, placing particular emphasis on the configuration of the front-end along with some of the general principles which influenced its design. In addition, a short discussion of the performance of this system during the initial 1987 Collider run is included. (author). 2 refs, 1 fig

[en] In Brazil, the Pocos de Caldas plateau presents an opportunity for a risk evaluation. This very well known region of high natural radioactivity has been used over the last two decades for intensive agricultural production as well as for the operation of a uranium mining and milling facility. Moreover, different risk perceptions exist between the operation of nuclear facilities and enhanced exposure to natural radiation. These aspects are of prime concern, since they are basic to quantifying and comparing the additional acceptable risks to be considered in a decision making process. 8 refs, 2 tabs

[en] The stanford Linear Collider (SLC) collides a beam of electrons and positrons at 92 GeV. It is the first colliding linac, and produces Z⁰ particles for High-Energy Physics measurements. The energy of each beam must be measured to one part in 10⁴ on every collision (120 Hz). An Energy Spectrometer in each beam line after collision produces two stripes of high-energy synchrotron radiation with critical energy of a few MeV. The distance between these two stripes at an imaging plane measures the beam energy. The Wire- Imaging Synchrotron Radiation Detector (WISRD) system comprises a novel detector, data acquisition electronics, readout and analysis. The detector comprises an array of wires for each synchrotron stripe. The electronics measure secondary emission charge on each wire of each array. A Macintosh II (using THINK C, THINK Class Library) and DSP coprocessor (using ANSI C) acquire and analyze the data, and display and report the results for SLC operation

No abstract available

[en] VERITAS is a ground-based gamma-ray observatory covering energies between 100 GeV and 50 TeV and will start operating by January 2007. We give a brief report of the construction status and performance characteristics of the telescopes

[en] The comprehensive data obtained for different rivers after the Chernobyl accident, primarily the data from the heavily contaminated Pripyat river-Dnieper river-reservoir system, provide a unique basis for validations and improvements of transport models for aquatic radionuclides. These data were used in two scenarios by the River Sub-Group of the Aquatic Working Group of the IAEA/CEC co-ordinated research programme Validation of Environmental Model Predictions (VAMP). For one model validation scenario, the Clinch River-Tennessee River system, contaminated by releases from the Oak Ridge National Laboratory, was chosen. The data collected during the post-Chernobyl period, related to the Pripyat river and to the Dnieper river and reservoirs, were used in the other scenario. Different kinds of models were applied, and the data from the two scenarios were used to simulated the dynamics of radionuclides in water, suspended sediments and bottom sediments. Analytical models, two kinds of box models and two kinds of one-dimensional (cross-sectionally averaged) models were used for the simulation of radionuclide concentrations in water and sediments. These models represented different levels of model complexity for the description of interactions between radionuclides, suspended sediments and sediments deposited on the bottom layer. The vertical profiles of radionuclides in bottom sediments were simulated for the Tennessee River scenario by the multilayers bottom model and by two kinds of vertical diffusion models. For this scenario, the modelling of radionuclide distribution in the aquatic food-chain, mainly in fish, was based on static approaches. For the other scenario, the temporal changes in ¹³⁷Cs concentrations in bream, trench and Carpio carpius in the Kiev reservoir (Dneiper river) were simulated by the dynamic model. The doses to the population via aquatic pathway were calculated on the basis of simulated concentrations in an environmental compartment and were used in analyses of the role of aquatic pathways in the formation of the total radiation dose after large releases. (author). 12 refs, 4 figs