David R. Quarrie

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BABAR, the detector for the SLAC PEP-II asymmetric eþe B Factory operating at the Uð4SÞ resonance, was designed to allow comprehensive studies of CP-violation in B-meson decays. Charged particle tracks are measured in a multi-layer silicon vertex tracker surrounded by a cylindrical wire drift chamber. Electromagnetic showers from electrons and photons are(More)
Developers and users of high-performance distributed systems often observe performance problems, the reasons for which are rarely obvious. Bottlenecks can occur in any of the components along the paths through which the data flows: the applications, the operating systems, the hosts, or the network. We have developed a methodology, known as NetLogger, for(More)
The BABAR database, based upon the Objectivity OO database management system, has been in production since early 1999. It has met its initial design requirements which were to accommodate a 100Hz event rate from the experiment at a scale of 200TB per year. However, with increased luminosity and changes in the physics requirements, these requirements have(More)
The Atlas collaboration at CERN[1] has adopted the Gaudi software architecture which belongs to the blackboard family: data objects produced by knowledge sources (e.g. reconstruction modules) are posted to a common in-memory data base from where other modules can access them and produce new data objects. The StoreGate has been designed, based on the Atlas(More)
We present measurements of time-dependent CP-violating asymmetries in neutral B decays to several CP eigenstates. The measurement uses a data sample of 23x10(6) Upsilon(4S)-->BbarB decays collected by the BABAR detector at the PEP-II asymmetric B Factory at SLAC. In this sample, we find events in which one neutral B meson is fully reconstructed in a CP(More)
The BaBar database has pioneered the use of a commercial ODBMS within the HEP community. The unique object -oriented architecture of Objectivity/DB has made it possible to manage over 700 terabytes of production data generated since May'99, making the BaBar database the world's largest known database. The ongoing development includes new features,(More)
We describe the initial work of the PASS Project which uses techniques from distributed object managment to analyze experimental data from high energy physics. A t this time, we have designed two prototypes to analyze high energy physics data from the CDF experiment at Fermi Lab. The data from this experiment consists of ((events” which describe particle(More)
The BABAR experiment at the PEP-II collider at SLAC is using an object database management system for its primary event store as well as for the storage of calibration and alignment information. We report on the experience gained since the experiment detected its first physics event in May 1999. This includes an overview of the software design, the hardware(More)
The GAUDI architecture and framework are designed to provide a common infrastructure and environment for simulation, filtering, reconstruction and analysis applications. Initially developed for the LHCb experiment, GAUDI has been adopted and extended by the ATLAS experiment and adopted by several other experiments including GLAST and HARP. We describe the(More)