Configuration of the ATLAS Trigger System

In this paper a conceptual overview is given of the software foreseen to configure the ATLAS trigger system. Two functional software prototypes have been developed to configure the ATLAS Level-1 emulation and the High-Level Trigger software. Emphasis has been put so far on following a consistent approach between the two trigger systems and on addressing their requirements, taking into account the specific use-case of the `Region-of-Interest' mechanism for the ATLAS Level-2 trigger. In the future the configuration of the two systems will be combined to ensure a consistent selection configuration for the entire ATLAS trigger system.Comment: Talk from the 2003 Computing in High Energy and Nuclear Physics (CHEP03), La Jolla, Ca, USA, March 2003, 8 pages, LaTeX, 9 eps figures. PSN THGT01

Charm counting in b and c events at LEP

In this article the current status of the partial width R/sub c//sup 0/ of the Z/sup 0/ to cc and of the multiplicity n/sub c/ of charm quarks per b decay are discussed. Final results presented by the LEP experiments using their full LEP 1 data sets lead to a more precise determination of both quantities. The new LEP and SLC averages are R /sub c//sup 0/=0.1674+or-0.0038 and n/sub c/=1.149+or-0.036. (18 refs)

The DELPHI Silicon Tracker in the global pattern recognition

ALEPH and DELPHI were the first experiments operating a silicon vertex detector at LEP. During the past 10 years of data taking the DELPHI Silicon Tracker was upgraded three times to follow the different tracking requirements for LEP 1 and LEP 2 as well as to improve the tracking performance. Several steps in the development of the pattern recognition software were done in order to understand and fully exploit the silicon tracker information. This article gives an overview of the final algorithms and concepts of the track reconstruction using the Silicon Tracker in DELPHI.Comment: Talk given at the 8th International Workshop on Vertex Detectors, Vertex'99, Texel, Nederland

Fracture initiation in Viscoelastic Solids

The subject of this paper is to derive generalized analytical expressions to predict fracture in viscoelastic polymer materials. To aid in understanding behavioral characteristics of viscoelastic materials, a basic background of viscoelastic models and their responses are presented and briefly discussed. Fracture from two types of cracks are considered; the first 1s a penny-shaped crack in a three-dimensional solid and the second is a crack the thickness of the material in a two-dimensional solid. Except for the constants, the same equations describe fracture in both 2-D and 3-D solids. The fracture equations were developed using expressions from Sneddon, Wnuk, Griffith and the theory of elasticity. (See more in text

A Plant Life Management Model Including Optimized MS&I Program - Safety and Economic Issues

This report collects the experience of the European Countries in the field of Plant Life Management (PLIM) and maintenance optimisation, as a background for the development of a new PLIM models, suitable for the European framework. The research highlights the the basic goal of PLiM in terms of support to a safe long-term supply of electricity in an economically competitive way. A PLIM model is proposed, validated with the experience of the SENUF research network members and with the essential contribution of managers and staff of a selected nuclear plant. The model addresses both technical and economic issues, as well as organizational and knowledge management issues and is now open for a broader validation by the research and engineering communities, to be carried out in the coming research steps.JRC.F.5-Nuclear operation safet

Quantum effects on plasma screening for thermonuclear reactions in laser-generated plasmas

A quantum plasma screening model based on the density matrix formalism is used to investigate theoretically the thermonuclear reactions $^{13}$C($\alpha$, $n$)$^{16}$O and $^2$H($d$, $n$)$^3$He in laser-generated plasmas over a large range of densities and temperatures. We find that for cold and dense (solid-state density) plasmas, the quantum model predicts plasma screening enhancement factors up to one order of magnitude larger than the ones from classical plasma models. Our results indicate that quantum effects can enhance the plasma screening for thermonuclear reactions, with potential also for industrial fusion energy gain. We put forward a possible experimental test of the screening theory in laser-generated plasmas which could also confirm predictions from nuclear astrophysics.Comment: 6 pages, 2 figures, 1 tabl