A Software Environment for the NA49 TPCs

In the collision of ultrarelativistic lead ions with nuclear targets at the CERN SPS up to several thousand charged particles in the momentum range of 0.1–200 GeV/c are produced. These events have been recorded by the large-volume tracking detectors (TPCs) of the experiment NA49. In order to analyse the huge amount of data (typically 10 TBytes per run) a software environment was developed at the University of Frankfurt. This system describes the detector information, basic data types and their relationships as C structures. The structure management is based on the dynamical memory management available in C. The implementation as a client-server architecture allows mixed-language programming and sharing of resources like visualization applications. Client and server communicate by standard UNIX network tools, thus providing interoperability between applications on different machines in heterogeneous distributed environments.