Software for the CMS Cosmic Challenge

At the end of 2004 CMS decided to redesign its offline software framework. The new software now includes a completely revisited event data model and is fully integrated with a database infrastructure for handling calibration and alignment data. This new software will be used in the first months of 2006 for the so called Magnet Test Cosmic Challenge (MTCC). The MTCC is a slice test in which a small fraction of all the CMS detection equipment is expected to be operated in the 4 T solenoid of the experiment. Cosmic rays detected in the muon chambers will be used to trigger the readout of all detectors in the general data acquisition system. Prior to data taking, the detectors and their readout electronics must be tuned and synchronized with dedicated software procedures. Local reconstruction must be carried out online and offline in all sub-detectors for event selection and monitoring purposes. Global reconstruction, linking different sub-detectors, is expected to be performed mainly offline. One of the main goals of the offline analysis of the MTCC data is the validation of the muon hardware alignment system functionality. A number of visualization tools are also expected to be used for validation purposes and monitoring.