Up to Offline Software
The goal of the recontruction is to convert hits in the detectors into "physics events" containing lists of particles attached to vertices.
Hits in the FDC strips are associated together into clusters in the DFDCCathodeCluster factory. Clusters and anode wires are matched to form "space points" in the DFDCPseudo factory. These space points are linked together within each FDC package into track segments in the DFDCSegment factory. Finally these track segments are linked together to form track candidates from the FDC alone. Similarly, hits in the axial layers of the CDC are associated together into "segments" and matched with stereo layers to form track candidates from the CDC alone. At this stage we use a helical model for the particle trajectories. Next FDC and CDC track candidates are merged and the final list of track candidates is constructed in the DTrackCandidate factory. Track fitting using the full magnetic field map and the material properties of the detector takes place in two stages: a wire-based pass that uses the wire positions (and the position along the wires in the FDC case) but not the drift times and a time-based pass incorporating the drift time information into the fit.