next up previous
Next: Clusterfinding Module TCL Up: Table structures Previous: Sequence and Cluster

Hit table

The reconstructed hit data is stored in the TPHIT table, whose entries are listed in Figure 5.

Figure 5: Structure used for tabulating TPC hit data.

All fields listed are filled by the hitfinder (TPH) module, except for TRACK and ID_GLOBTRK, which are filled by the tracking and global tracking software, respectively.

The FLAG field is set to 0 (1) if the hit was extracted from a single-hit (multi-hit) cluster pattern. See below. This flag should be useful for analysis modules (e.g. particle identification modules based on gas ionization, and some kink-finding modules) whose performance may improve if they only use ``clean'' hits.

The fields containing crossing angle information, ALPHA and LAMBDA, are filled in the hitfinder based on the shape of the hitpattern (see below), and are currenly overwritten by the tracking software if the hit is associated with a reconstructed track.

The following fields are currently not being filled and may eventually be eliminated from the table: DQ, DALPHA, DLAMBDA.

Michael A. Lisa
Tue Feb 6 15:49:35 EST 1996