4.4 Patch SGVTRKER : Tracking routines

This patch contains the code for tracking charged particles through the detector, and determining with what precision they can be measured. The track parameters can optionally also be smeared according to the covariance matrix determined. This smearing will take the correlation of the 5 helix parameters correctly into account. Code also exists to do extrapolations only (ie. without error estimates), and to access the geometry of the detector.

Entry points :

ZTINI (see 4.4.55)

(initialisation)

ZTTRAK (see 4.4.1)

(Follow charged particle)

ZTFOLN (see 4.4.3)

(Follow neutral particle)

ZTERRM (see 4.4.2)

(calculate error-matrix)

ZTTISC (see 4.4.5)

(Extrapolation only)

ZTTISP (see 4.4.7)

(Extrapolation only)

ZTTCYL (see 4.4.6)

(Ditto)

ZTTPLA (see 4.4.8)

(Ditto)

ZTTDST (see 4.4.9)

(Ditto)

ZTTRIP (see 4.4.10)

(Ditto)

access routines to geometry data :

               ZTCNAM, ZTPNAM, ZTCRAD, ZTCLEN, ZTPLAZ, ZTPRAD,
               ZTCERF, ZTCEZ, ZTPERX, ZTPERY, ZTISCB, ZTISCF,
               ZTCSDE, ZTCEFF, ZTCTHR, ZTCEFF, ZTCRES, ZTCTYP,
               ZTCX0, ZTPX0, ZTCANB, ZTPANB, and ZTTINF

The patch does not call code in other patches.

The communication with the caller is through arguments only (however, the detector geometry is loaded from an external file)