122695581
TOWARDS COST-TO-PERFORMANCE OPTIMISATION OF LARGE SUPERFLUID HELIUM REFRIGERATION SYSTEMS
The field range of superconducting devices may be extended by lowering their operating temperature, using superfluid helium refrigeration systems which have to deliver working pressures down to 1.6 kPa. The corresponding pressure ratio can be produced by integral cold compression or using a combination of cold compressors in series together with "warm" compressors at room temperature. The optimisation of such a system depends on the number, arrangement and characteristics of cold and warm machines as well as on the operating scenario and turndown capability. The aim of this paper is to compare relative investment and operating costs of different superfluid helium cryogenic systems, with the aim of optimising their cost-to-performance ratio within the constraints of their operating scenario.
115884934
Operational experience with the LEP low-beta superconducting quadrupoles
59802398
Open inventor and virtual reality at Fermilab
We discuss our experiences with Open Inventor and with basic tools and techniques of Virtual Reality, including some preliminary results from an immersive system.
109697769
Report of the working group on detector simulation
An ad hoc group at Snowmass reviewed the need for detector simulation to support detectors at the SSC. This report first reviews currently available programs for detector simulation, both those written for single specific detectors and those aimed at general utility. It then considers the requirements for detector simulation for the SSC, with particular attention to enhancements that are needed relative to present programs. Finally, a list of recommendations is given.
54039880
Using workstation GUIs in HEP, X-Windows, Motif and the Nirvana project
We present four small, high quality, Motif based tools for high energy physicists and discuss some of the less obvious work that is necessary to fully take advantage of graphical user interfaces (GUIs). Histo-Scope and NPlot are interactive data display programs. Histo-Scope is for viewing data as it is collected in running analysis or data acquisition programs, NPlot, for plotting data from text files. Visajet is an interface for the ISAJET event simulation program. It gives users a fast way to configure ISAJET and displays ISAJET events in a three dimensional phase space display that users can rotate and manipulate with the mouse. NEdit is a GUI style plain text editor.
120234331
Performances of a preamplifier-silicon photodiode readout system associated with large BGO crystal scintillators
Abstract The characteristics of a hybridized low noise preamplifier are described. Performances of the preamplifier in combination with silicon photodiodes are discussed and results from laboratory tests and test runs with an assembly of large BGO crystals are presented.
120906556
THE BTEV TRIGGERS AND DATA ACQUISITION SYSTEMS
A coherent and complete suite of triggers and data compression stages for the BTeV experiment has been designed and prototyped. Level 1 considers all crossings, finds primary vertices, and searches for detached tracks from these primary vertives using only the pixel vertex detector. Muons with a relatively high transverse momentum will also be identified at that stage. Level 1 runs on dedicated processors. Level 2 selects events based on the pixel and the forward tracking systems, and will run on a conventional processor farm. Level 3 will use the complete BTeV detector information to reduce the background by a factor of factor 2 to 5 and to reduce significantly the event size.