Object Database for Constants: The common CLEO Online and Offline solution

Abstract

After the successful conclusion of the CLEO III phase, the CLEO experiment at the Cornell Electron Positron Storage Ring CESR is preparing for its transition to CLEO-c. This new program contains a wide array of Physics studies at e+ e- collisions at center of mass energies between 3 GeV and 5 GeV that will provide new insights into QCD. Because the existing Silicon Vertex Detector needed to be replaced within a short time, a 6 layer vertex drift chamber has been installed in spring 2003. At the same time, the existing Ring Imaging Cherenkov Detector, along with a conventional drift chamber, E.M. calorimeter and muon chambers, will continue to be part of the experiment. The CLEO Constants Database system must provide efficient access to detector and analysis constants for a wide variety of purposes, such as hardware configuration, Online operation and monitoring, calibration, and the complete CLEO analysis framework. Since the original project, implemented through the Objectivity Object Database Management System, did not meet those requirements, the system was redesigned from the ground up, using the same technology. It is currently being introduced into the production environment without significant interruptions. In this presentation, we will outline the specifications of the constants database system, and then report on the process that led to the redesign. Performance comparisons and insights on relevant design aspects will be shown.